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Tropical Weather Outlook NWS National Hurricane Center Miami FL 200 PM EDT Sat Nov 5 2022 1. Southwestern Atlantic: A trough of low pressure located over the eastern Caribbean Sea is producing a large area of disorganized showers and thunderstorms. The trough is forecast to move northward over the southwestern Atlantic by Sunday, where a broad area of low pressure is expected to form north of Hispaniola. Environmental conditions are forecast to be conducive for gradual development, and a subtropical or tropical depression could form during the early part of next week while the system moves generally westward to west-northwestward over the southwestern Atlantic. Regardless of development, there is an increasing risk of coastal flooding, gale-force winds, heavy rainfall, rough surf, and beach erosion along much of the southeastern United States coast, the Florida east coast, and portions of the central and northwestern Bahamas during the early to middle part of next week. The disturbance is also expected to bring locally heavy rainfall to Puerto Rico and the Virgin Islands this weekend. Interests in those areas should monitor the progress of this system. * Formation chance through 48 hours...medium...40 percent. * Formation chance through 5 days...high...70 percent.

Now up to 50% in the 5 day: 8PM TWO Southwestern Atlantic: A large non-tropical low pressure system is expected to develop across the northeastern Caribbean Sea and southwestern Atlantic by the latter part of the weekend. The system is initially expected to be very broad and disorganized. However, it could begin to acquire subtropical or tropical characteristics during the early part of next week, and a subtropical or tropical depression could form during the early to middle portion of next week while the system moves generally westward to west-northwestward over the southwestern Atlantic. Regardless of development, there is an increasing risk of coastal flooding, gale-force winds, heavy rainfall, rough surf, and beach erosion along much of the southeastern United States coast, the Florida east coast, and portions of the central and northwestern Bahamas during the early to middle part of next week. * Formation chance through 48 hours...low...near 0 percent. * Formation chance through 5 days...medium...50 percent.

The 12Z UKMET, which has a TS hitting Cape Canaveral at 144 moving NW, has at 168 a still well organized low S of Macon, GA, moving N. At that time, it's rain shield expands greatly with moderate to heavy rains all of the way from the NE GOM to NE AL/Atlanta to SW PA, east to DC, and south to most of VA and NC. This is ahead of a rapidly SEward moving strong cold front that extends from Ohio to TX. If it were to play out similarly, this could end up a pretty major event for much of the SE US, including providing much needed generous rains.

The 12Z UKMET, which as mentioned has a TS hitting Cape Canaveral at 144 moving NW, has at 168 a still well organized low S of Macon, GA, moving N. At that time, it's rain shield expands greatly with moderate to heavy rains all of the way from the NE GOM to Atlanta to SW PA, east to DC, and south to most of VA and NC. This is ahead of a rapidly SEward moving strong cold front that extends from Ohio to TX. If it ends up playing out similarly, this could end up a major event for much of the E US.

Model consensus is forecasting 500 mb heights that are as high as 2.5 SD above the mean for early November in the NE US Wednesday night. That is equivalent to saying 500 mb hts that are at the 99% percentile meaning hts that high or higher in early November there happen only 1% of the time. With that strong of a high to the north, the SW Atlantic/Bahamas/SE US is in a highly unusual pattern for early November as regards tropical potential. With only 8 TCs having formed since 1851 in the SW Atlantic Nov 1-10 (see link below) and considering this highly anomalous pattern, there's not much historical track data/climo to utilize to predict what will happen. So even though none of those 8 SW Atlantic originating TCs hit the US, that doesn't mean much in this very unusual pattern: https://www.nhc.noaa.gov/climo/images/nov_1_10.png If we incorporate the current SW Atlantic SSTs, we get even further from normal early Nov tropical potential. They're currently 28 to 29 C (82-84 F), which is ~1C/2F warmer than the normal and near the normal for mid October (normal found here): https://www.nhc.noaa.gov/gifs/SST/AL_10_OCT_1971-2000_RSST.gif Along with this very strong H5 ridge to the north and warm SSTAs, 200 mb wind speeds are forecasted to plunge well below normal early to mid next week in the SW Atlantic. So, shear may become unusually light then. Considering all of the above, the NHC has quite a challenge and will make forecasting discussions quite interesting.

Beside the just noted 12Z GFS landfalling at Jupiter, FL, late Thursday with a H, the 12Z CMC and UKMET both have a NW moving TS centered near Cape Canaveral at hour 144 (Thursday morning). Here is the 12Z UKMET: NEW TROPICAL CYCLONE FORECAST TO DEVELOP AFTER 90 HOURS FORECAST POSITION AT T+ 90 : 26.1N 71.5W LEAD CENTRAL MAXIMUM WIND VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS) -------------- ---- -------- ------------- ------------- 1200UTC 08.11.2022 96 26.0N 72.6W 1007 32 0000UTC 09.11.2022 108 25.3N 74.0W 1007 35 1200UTC 09.11.2022 120 26.2N 75.1W 1006 39 0000UTC 10.11.2022 132 27.0N 78.1W 1004 40 1200UTC 10.11.2022 144 28.5N 80.8W 1003 42

From NWS Charleston, SC: gales and major coastal flooding possible Mon-Wed for SC/GA and this may occur even if there is no actual STC or TC: TIDES/COASTAL FLOODING ASTRONOMICAL TIDE LEVELS ARE RISING AS FULL MOON ON NOVEMBER 8TH APPROACHES. ADDITIONALLY, PERSISTENT MODERATE TO STRONG NORTHEAST WINDS WILL CAUSE TIDAL ANAMOLIES TO INCREASE. BY EARLY NEXT WEEK AN EVEN STRONGER NORTHEAST FLOW COULD PRODUCE SUBSTANTIAL ANOMALIES THAT MAY RESULT IN MODERATE TO MAJOR COASTAL FLOODING AT THE CHARLESTON HARBOR TIDE GAUGE. COASTAL FLOODING COULD BEGIN TODAY ALONG COASTAL CHARLESTON AND COLLETON COUNTIES AND AS EARLY AS SATURDAY EVENING FOR THE FAR SOUTHERN SOUTH CAROLINA AND MUCH OF THE GEORGIA COAST. THE MORE SIGNIFICANT TIDE LEVELS COULD BEGIN AS EARLY AS MONDAY EVENING AND CONTINUE THROUGH WEDNESDAY OR THURSDAY. A SERIES OF COASTAL FLOOD ADVISORIES AND POSSIBLY COASTAL FLOOD WATCHES/WARNINGS MAY WILL BE NEEDED.

From NWS Charleston, SC: gales and moderate to major coastal flooding possible Mon-Wed for SC/GA and this may occur even if there is no actual STC or TC: TIDES/COASTAL FLOODING ASTRONOMICAL TIDE LEVELS ARE RISING AS FULL MOON ON NOVEMBER 8TH APPROACHES. ADDITIONALLY, PERSISTENT MODERATE TO STRONG NORTHEAST WINDS WILL CAUSE TIDAL ANAMOLIES TO INCREASE. BY EARLY NEXT WEEK AN EVEN STRONGER NORTHEAST FLOW COULD PRODUCE SUBSTANTIAL ANOMALIES THAT MAY RESULT IN MODERATE TO MAJOR COASTAL FLOODING AT THE CHARLESTON HARBOR TIDE GAUGE. COASTAL FLOODING COULD BEGIN TODAY ALONG COASTAL CHARLESTON AND COLLETON COUNTIES AND AS EARLY AS SATURDAY EVENING FOR THE FAR SOUTHERN SOUTH CAROLINA AND MUCH OF THE GEORGIA COAST. THE MORE SIGNIFICANT TIDE LEVELS COULD BEGIN AS EARLY AS MONDAY EVENING AND CONTINUE THROUGH WEDNESDAY OR THURSDAY. A SERIES OF COASTAL FLOOD ADVISORIES AND POSSIBLY COASTAL FLOOD WATCHES/WARNINGS MAY WILL BE NEEDED.

Webb's tables go back to 1850. Based on his tables for that period, there was actually one quad or even quint dip (depending on how one might count it) cold ENSO although it just missed being a quad dip La Niña. Instead, it was a triple dip weak La Niña with dips centered on March of 1873, March of 1874, and September of 1874. Then there were dips in August of 1875 and May of 1876 that were to -0.6 C, but these two dips were barely too short-lived to count as La Niña. Fwiw, I treat this period as a quad dip cold ENSO based on number of consecutive fall/winter periods: 1872-3 through 1875-6. It had trimonths that were -0.1 C or colder from JFM of 1872 all the way through JAS of 1876. That's ~4.5 years of cold ENSO uninterrupted. Webb's tables have one triple peak El Niño: 1939-40 through 1941-2. Also, I see a couple of three consecutive fall/winter warm ENSO periods: - 1883-4 (warm neutral) followed by 1884-5 & 1885-6 both being El Niño; this period had +0.1+ C JFM of 1883 through JFM of 1886 meaning three years uninterrupted. - 1864-5 and 1865-6 were both El Niño followed by 1866-7 being warm neutral. This period had +0.1+ C from JJA of 1864 through JFM of 1867 (2 years, 7 months uninterrupted). So, I count a total of three triple peak warm ENSO periods since 1850. But I count nine triple dip cold ENSO periods (including the current one and also the one quad as noted). So, 9-3 in favor of the triple dips vs triple peaks. Reason: I don't know. Possibly random? If triple dips and triple peaks happened to have about the same true probability, getting 75% of them one way vs 25% the other way in a sample size of only 12 isn't that far fetched. So, we really don't know for sure that the underlying true chance for a triple dip is higher than that for a triple peak. Or maybe it really is higher but not by much. However, my wild guess is that it is somewhat higher fwiw. Looking at his tables, I count ~45 fall/winters that are La Niña and El Niño, respectively. Looking at the NOAA ONI table for 1950+, I count 27 La Niña and 26 El Niño. So, the underlying true probability of each in any one fall/winter would at least appear to be similar. Webb's Nino 3.4 based ENSO tables: https://www.webberweather.com/ensemble-oceanic-nino-index.html

The 18Z GEFS is still another run that suggests significant effects (rain and wind) quite possible over E FL on US Election Day, something that could reduce turnout. Reduction % in turnout due to wx tends to not be equal for all sides. Thus it could have a significant effect on the outcome of close races. I looked back every two years to see if there were any previous US Election Days marred by an Atlantic basin tropical or subtropical cyclone. I found none affecting the lower 48 states. But I did find 1984's TS Klaus (see link below) that directly affected PR on Election Day (11/6). So, this system could make history in the lower 48 as very likely the first Atlantic TC or STC affecting a portion on Election Day. 1984's Klaus track is here:

After three very wet months that brought my water table very high in early Sept, I measured rainfall during only one period in October, the night of 10/12-13, and it was 0.45". This compares to a normal of nearly 4"! It looks like the dryness of La Niña, which had made it extremely dry here from the middle of Nov of last year through May of this year, has taken back over. Actually, going way back to September 11th, I've received a mere 1.25" and that includes 0.75" from Ian! It was a pleasantly cool October with lows ~5 BN and highs ~2 BN yielding a greater than normal October daily range due to the dryness. It was easily the coolest October since 2011.

For a good portion of the SE US, the thread linked below covers the near unanimous model prog for the development of a complex storm system this weekend in the NE Caribbean to SW Atlantic corridor. The models then move it NW toward the SE coast next week underneath a strong E US H5 to surface ridge. It could impact part of the SE as early as Election Day, especially near the coast and with highest chance of having significant impact that early in FL. Thus, inclement weather, which often has a noticeable effect on turnout even with just mundane systems, could turn out to be a major factor for certain SE US races, especially in FL. The system as depicted would very likely be subtropical and/or tropical at various timeframes:

New topic for this:

The models are pretty much unanimous on a complex storm system forming this weekend in the NE Caribbean or the SW Atlantic, which could then move NW to the SE US next week per model consensus. Subtropical and/or tropical cyclone development is very possible, if not likely. Thus, this could conceivably have a significant effect on SE US weather, especially near the Atlantic coast, on Election Day. This is from the 2PM TWO: 1. Southwestern Atlantic: A complex, non-tropical area of low pressure is expected to develop this weekend over the northeastern Caribbean Sea or the southwestern Atlantic. Some slow subtropical or tropical development of this system is possible afterward while it moves generally northward to northwestward through early next week. * Formation chance through 48 hours...low...near 0 percent. * Formation chance through 5 days...low...20 percent.

11/2/2022 is the first day on record with two hurricane designations on the same day in November. There have been only two other years on record with two simultaneous hurricanes in November: 1932 and 2001. But 2001's/1932's November hurricanes were designated three/four days apart. The latest date for two simultaneous hurricanes on record is November 10th, set in 1932. Next latest is November 5th, set in 2001.

Update based on the near 100% expectation that Lisa will end up having significant land impacts: For the years 1995-2022, there have been 14 La Niña seasons. Out of these 14, only two had no significant western basin land impacts from TCs with TCG 10/22+: 1995 and 2000. The precursor to Wanda in 2021 (Invest 94L starting off NC) was very strong (winds over 100 mph in Mass.) and thus was counted. The last 10 La Niña seasons in a row (back to 2005) have fallen into this late impact category.

BULLETIN Tropical Storm Lisa Advisory Number 6 NWS National Hurricane Center Miami FL AL152022 1100 PM EDT Mon Oct 31 2022 ...LISA FORECAST TO STRENGTHEN AS IT APPROACHES CENTRAL AMERICA... ...HURRICANE WATCH REMAINS IN EFFECT FOR BELIZE AND THE BAY ISLANDS OF HONDURAS... SUMMARY OF 1100 PM EDT...0300 UTC...INFORMATION ----------------------------------------------- LOCATION...15.6N 79.1W ABOUT 290 MI...470 KM SSE OF GRAND CAYMAN ABOUT 615 MI...990 KM E OF BELIZE CITY MAXIMUM SUSTAINED WINDS...45 MPH...75 KM/H PRESENT MOVEMENT...W OR 270 DEGREES AT 12 MPH...19 KM/H MINIMUM CENTRAL PRESSURE...1002 MB...29.59 INCHES Tropical Storm Lisa Discussion Number 6 NWS National Hurricane Center Miami FL AL152022 1100 PM EDT Mon Oct 31 2022 Lisa is gradually becoming better organized with the associated convection deepening and expanding around the center. However, the system still lacks banding features. The Air Force Hurricane Hunters are currently investigating Lisa and so far have found flight-level winds as high as 46 kt and peak SFMR winds of about 35 kt. This data supports maintaining the initial intensity of 40 kt. The tropical storm is moving westward at about 10 kt. The track forecast reasoning seems fairly straightforward. A low- to mid-level ridge situated to the north of Lisa is expected to build westward. This pattern should keep the storm on a steady westward path, bringing the core of the cyclone near or just north of the Bay Islands of Honduras late Tuesday night/early Wednesday and across Belize by late Wednesday. The models are in fairly good agreement through landfall, and the NHC track forecast is very similar to the previous one during the next couple of days. After landfall, the models diverge with some solutions showing a northwest track and others a southwest motion. The NHC track forecast continues to split the difference, and it is a touch south of the previous one to be a little closer to the various consensus models. The environmental conditions appear relatively favorable for Lisa to strengthen during the next 36 to 48 hours. SSTs are quite warm beneath the cyclone and the vertical wind shear is expected to be low to moderate. There is some dry air near the system, however, which might slow the rate of intensification. The NHC intensity forecast follows the trend of the consensus models and continues to show Lisa becoming a hurricane when it is over the Gulf of Honduras early Wednesday, and it is expected to maintain that intensity when it makes landfall. Rapid weakening is expected after the system moves inland, and even though the forecast shows a 96-h point, it is certainty possible that Lisa could have dissipated by then. Key Messages: 1. Hurricane conditions are possible in the Bay Islands of Honduras early Wednesday and along the coast of Belize by Wednesday afternoon, where a Hurricane Watch is in effect. 2. Tropical storm conditions are expected along portions of the north coast of Honduras, where a Tropical Storm Warning has been issued. A Tropical Storm Watch is in effect for the remainder of the coast of Honduras, the Caribbean coast of Guatemala, and the southeastern Yucatan Peninsula of Mexico, where tropical storm conditions are possible. 3. Localized flash flooding is expected across portions of the eastern Yucatan Peninsula, Belize, and northern Honduras, including the Bay Islands, starting late Tuesday continuing through Thursday. 4. There is potential for a dangerous storm surge near where the core of Lisa crosses the coast of Belize. FORECAST POSITIONS AND MAX WINDS INIT 01/0300Z 15.6N 79.1W 40 KT 45 MPH 12H 01/1200Z 16.0N 81.3W 45 KT 50 MPH 24H 02/0000Z 16.4N 83.9W 55 KT 65 MPH 36H 02/1200Z 16.8N 86.3W 65 KT 75 MPH 48H 03/0000Z 16.9N 88.3W 65 KT 75 MPH...INLAND 60H 03/1200Z 16.8N 89.8W 40 KT 45 MPH...INLAND 72H 04/0000Z 16.8N 91.2W 25 KT 30 MPH...POST-TROP/REMNT LOW 96H 05/0000Z 17.0N 93.5W 20 KT 25 MPH...POST-TROP/REMNT LOW 120H 06/0000Z...DISSIPATED $$ Forecaster Cangialosi

BULLETIN Tropical Storm Lisa Advisory Number 4 NWS National Hurricane Center Miami FL AL152022 1100 AM EDT Mon Oct 31 2022 ...DISTURBANCE BECOMES TROPICAL STORM LISA IN THE CENTRAL CARIBBEAN SEA... ...EXPECTED TO GRADUALLY STRENGTHEN OVER THE NEXT FEW DAYS... SUMMARY OF 1100 AM EDT...1500 UTC...INFORMATION ----------------------------------------------- LOCATION...15.5N 77.3W ABOUT 175 MI...285 KM S OF KINGSTON JAMAICA ABOUT 365 MI...590 KM SE OF GRAND CAYMAN MAXIMUM SUSTAINED WINDS...40 MPH...65 KM/H PRESENT MOVEMENT...W OR 270 DEGREES AT 14 MPH...22 KM/H MINIMUM CENTRAL PRESSURE...1003 MB...29.62 INCHES ------------------------- Tropical Storm Lisa Discussion Number 4 NWS National Hurricane Center Miami FL AL152022 1100 AM EDT Mon Oct 31 2022 GOES-16 1-minute visible imagery indicates that the low-level circulation of the system has closed off again, although the system is still a bit elongated north-to-south. Westerly shear has caused the center to be exposed to the west and north of the primary convective banding features. NOAA Hurricane Hunter tail Doppler radar data also show that the low is tilted southeastward with height, a reflection of the current shear. Still, the plane had numerous SFMR values of around 35 kt, and dropsonde data showed the pressure has dropped to 1003 mb. These values are sufficient to call the system a tropical storm with an initial wind speed of 35 kt. After a dip southward overnight, Lisa is moving westward again at about 12 kt. The storm should move westward to west-northwestward for the next day or two under a mid-level ridge to the north. As the ridge intensifies in a few days, Lisa is likely to move westward, or possibly a little south-of-west, while it approaches Belize. Model guidance remains in very good agreement, and only a small southward adjustment was made to the previous forecast. Lisa should encounter more conducive atmospheric and oceanic conditions for the next few days, with increasing mid-level humidities and generally lower shear. The storm will likely still have some bouts with drier air infiltrating in the northwestern quadrant of the circulation, but the diminishing shear should lessen the impact of this factor. Thus slow intensification is shown for the next few days, consistent with the interpolated previous forecast. It should be noted that the new NHC forecast is on the high side of the guidance for this cycle, with a notable decrease of the forecast intensity in many of the models. The official forecast is lower than the previous one, owing to the model trend, but it is preferable to wait another cycle to make any larger changes after the model suite ingests the plentiful aircraft data for the 12 UTC suite. Key Messages: 1. Tropical storm conditions are possible on Jamaica today. 2. Interests along the coast of Central America, especially near Belize and the Yucatan Peninsula of Mexico, should monitor the progress of this system. Additional watches and warnings will likely be required by late today. FORECAST POSITIONS AND MAX WINDS INIT 31/1500Z 15.5N 77.3W 35 KT 40 MPH 12H 01/0000Z 15.8N 79.0W 40 KT 45 MPH 24H 01/1200Z 16.3N 81.4W 45 KT 50 MPH 36H 02/0000Z 16.8N 83.9W 50 KT 60 MPH 48H 02/1200Z 17.1N 86.3W 55 KT 65 MPH 60H 03/0000Z 17.1N 88.2W 65 KT 75 MPH 72H 03/1200Z 16.7N 90.0W 40 KT 45 MPH...INLAND 96H 04/1200Z...DISSIPATED

BULLETIN Potential Tropical Cyclone Fifteen Advisory Number 2 NWS National Hurricane Center Miami FL AL152022 1100 PM EDT Sun Oct 30 2022 ...NOAA HURRICANE HUNTER AIRCRAFT REPORTS LITTLE CHANGE IN THE DISTURBANCE... SUMMARY OF 1100 PM EDT...0300 UTC...INFORMATION ----------------------------------------------- LOCATION...15.8N 74.9W ABOUT 195 MI...315 KM SE OF KINGSTON JAMAICA ABOUT 480 MI...770 KM ESE OF GRAND CAYMAN MAXIMUM SUSTAINED WINDS...40 MPH...65 KM/H PRESENT MOVEMENT...W OR 280 DEGREES AT 12 MPH...19 KM/H MINIMUM CENTRAL PRESSURE...1005 MB...29.68 INCHES Potential Tropical Cyclone Fifteen Discussion Number 2 NWS National Hurricane Center Miami FL AL152022 1100 PM EDT Sun Oct 30 2022 Satellite imagery and data from a NOAA Hurricane Hunter aircraft indicate there has been little change in the structure of the disturbance this evening. Satellite imagery shows that the low-level center is apparent in satellite imagery between two areas of disorganized convection to the northwest of a loosely-curved convective band. The aircraft data shows that the circulation at 460 mb is located to the southeast of the surface center and is not well defined at that level. Dropsondes to the northeast of the center showed surface winds of 30 kt, and drops near the center suggest the central pressure is near 1005 mb. Based on these data, the initial intensity remains 35 kt. The estimated initial motion is a little to the left of the previous advisory, 280/10 kt. A general westward to west-northwestward motion is expected during the next 48 h or so due to the presence of a westward moving mid-level ridge north of the center. After that time, the ridge should build a little faster toward the west and southwest, resulting in a south of west motion as the system approaches Belize or the Yucatan Peninsula of Mexico just after 72 h. The forecast guidance has shifted southward through 60 h, and the new forecast track is nudged in that direction. However, the new track lies to the north of the various consensus models. It should be noted that the the forecast track could undergo some additional adjustments until the circulation center becomes better defined. A combination of the current disorganized structure, moderate west-northwesterly shear, and weakly convergent upper-level flow should limit intensification for the next 12-24 h. However, the system is still expected to become a tropical storm in about 12 h when the convection increases during the diurnal maximum. After 24 h, increased upper-level divergence, decreased shear, and better organization should allow a faster development rate, and the system is expected to steadily strengthen. The new intensity forecast follows the previous forecast in calling for the system to become a hurricane before landfall in Belize or the Yucatan Peninsula, with a forecast peak intensity of 70 kt being near the upper edge of the intensity guidance. No changes to the current watches are required at this time. A Tropical Storm Warning may be necessary for Jamaica Monday morning depending on the evolution of the track and the 34-kt wind radii. Key Messages: 1. Tropical storm conditions are possible within the Tropical Storm Watch areas beginning Monday for Jamaica and on Tuesday for Grand Cayman Island. 2. Interests along the coast of Central America, especially near Belize and the Yucatan Peninsula of Mexico, should monitor the progress of this system. Additional watches and warnings will likely be required early this week. FORECAST POSITIONS AND MAX WINDS INIT 31/0300Z 15.8N 74.9W 35 KT 40 MPH...POTENTIAL TROP CYCLONE 12H 31/1200Z 16.0N 76.4W 35 KT 40 MPH...TROPICAL CYCLONE 24H 01/0000Z 16.3N 78.4W 40 KT 45 MPH 36H 01/1200Z 16.7N 80.6W 45 KT 50 MPH 48H 02/0000Z 17.1N 83.1W 55 KT 65 MPH 60H 02/1200Z 17.3N 85.4W 65 KT 75 MPH 72H 03/0000Z 17.1N 87.4W 70 KT 80 MPH 96H 04/0000Z 16.0N 91.0W 30 KT 35 MPH...INLAND 120H 05/0000Z...DISSIPATED $$ Forecaster Beven

From what I've read, the northern burbs of Atlanta are largely near or nearing peak already here in late October. I don't think it has occurred this early in many years. This of course is due to the chilly late Sep to mid Oct. Back in much of the 1980s, there were some years that peaked there this early. But in most years since, the peak has been in early to mid Nov.

BULLETIN Potential Tropical Cyclone Fifteen Advisory Number 1 NWS National Hurricane Center Miami FL AL152022 500 PM EDT Sun Oct 30 2022 ...ADVISORIES INITIATED ON POTENTIAL TROPICAL CYCLONE FIFTEEN... ...TROPICAL STORM WATCHES ISSUED FOR JAMAICA AND GRAND CAYMAN ISLAND... SUMMARY OF 500 PM EDT...2100 UTC...INFORMATION ---------------------------------------------- LOCATION...15.7N 73.6W ABOUT 265 MI...425 KM SE OF KINGSTON JAMAICA ABOUT 560 MI...900 KM ESE OF GRAND CAYMAN MAXIMUM SUSTAINED WINDS...40 MPH...65 KM/H PRESENT MOVEMENT...WNW OR 290 DEGREES AT 10 MPH...17 KM/H MINIMUM CENTRAL PRESSURE...1005 MB...29.68 INCHES WATCHES AND WARNINGS -------------------- CHANGES WITH THIS ADVISORY: The government of Jamaica has issued a Tropical Storm Watch for the island of Jamaica. The government of the Cayman Islands has issued a Tropical Storm Watch for Grand Cayman Island. -------------------------- Potential Tropical Cyclone Fifteen Discussion Number 1 NWS National Hurricane Center Miami FL AL152022 500 PM EDT Sun Oct 30 2022 This morning we were fortunate to have concurrent NOAA and Air Force Reserve Hurricane Hunter missions, which provided a wealth of flight-level, Tail Doppler Radar, and dropsonde data over the system in the central Caribbean Sea. The data indicated that a well-defined, while somewhat broad, circulation had formed with a minimum pressure of 1005 mb. A combination of SFMR winds and surface dropsonde data also suggested that the system had 35-kt winds in its northern semicircle. With that said, the satellite presentation of the system currently lacks sufficient convective organization to be considered a tropical cyclone. However, given the well-defined center and tropical-storm-force winds, there is significant risk for tropical storm conditions in the near future in portions of Jamaica and Grand Cayman Island. With the expectation that this system will likely become a tropical storm soon, advisories have been initiated on Potential Tropical Cyclone Fifteen. The estimated motion of the disturbance is off to the west-northwest at 290/9 kt. This general motion is forecast to continue for the next day or so, as an expansive mid-level ridge is currently centered north of the system and expected to move westward with the cyclone. Toward the end of the forecast period, the ridge may nose further westward as a deep-layer trough becomes established well to the the northeast, which could result in a south of due west motion when the system approaches the coast of Belize. Landfall is expected between the 72- and 96-hour forecast points. The initial NHC track forecast is roughly a blend of the latest GFS and ECMWF guidance, which is also quite close to the HCCA and TCVA consensus aids. Based on the current structure, it may take a bit longer for the convection to become sufficently organized to allow the formation of a tropical cyclone, but this is forecast to occur at some point tonight, likely during the typical diurnal maximum. After deep convection become better established, environmental conditions appear to be conducive for further intensification, especially in the 24-48 hour period when the vertical wind shear is expected to be lowest (5-15 kt) as the system traverses 29-30 C sea-surface temperatures. Mid-level relative humidity is quite low (55-60 percent), but given the relatively low shear, this may act to keep the system's structure small with a constricted radius of maximum winds. The initial intensity forecast after 24 hours closely follows the latest HCCA and ICON intensity guidance, making the system a Category 1 hurricane in 60-72 hours. The system should weaken quickly over land and is forecast to dissipate before day 5. Based on the latest forecast, the government of Jamaica has issued a Tropical Storm Watch for Jamaica, and the government in the Cayman Islands has issued a Tropical Storm Watch for Grand Cayman Island. Key Messages: 1. Tropical storm conditions are possible within the Tropical Storm Watch areas beginning Monday for Jamaica and on Tuesday for Grand Cayman Island. 2. Interests along the coast of Central America, especially near Belize, should monitor the progress of this system. Additional watches and warnings will likely be required early this week. FORECAST POSITIONS AND MAX WINDS INIT 30/2100Z 15.7N 73.6W 35 KT 40 MPH...POTENTIAL TROP CYCLONE 12H 31/0600Z 16.0N 74.9W 35 KT 40 MPH...TROPICAL CYCLONE 24H 31/1800Z 16.3N 76.6W 40 KT 45 MPH 36H 01/0600Z 16.7N 78.8W 50 KT 60 MPH 48H 01/1800Z 17.2N 81.3W 60 KT 70 MPH 60H 02/0600Z 17.5N 83.6W 65 KT 75 MPH 72H 02/1800Z 17.4N 85.7W 70 KT 80 MPH 96H 03/1800Z 16.4N 89.5W 35 KT 40 MPH...INLAND 120H 04/1800Z...DISSIPATED $$ Forecaster Papin/Cangialosi

The first advisory on this will be issued at 5PM AST as PTC 15. It currently is still tilted due to shear.

8AM 8/30 TWO says better organized and could be a major flooding rainfall threat, which may be bad news for some areas and would imho make it thread worthy: 1. Central Caribbean: A broad area of low pressure over the central Caribbean Sea continues to produce disorganized showers and thunderstorms. However, overnight satellite wind data suggest the circulation is gradually becoming better defined. Environmental conditions are forecast to be conducive for additional development, and a tropical depression is likely to form in the next couple of days while the system moves west-northwestward at 10 to 15 mph over the central and northwestern Caribbean Sea. Interests in Jamaica should monitor the progress of this system. NOAA and Air Force Reserve Hurricane Hunter aircraft will be investigating the system this morning. Regardless of development, locally heavy rainfall is possible over portions of the Lesser Antilles, the Virgin Islands, Puerto Rico, Hispaniola, and Jamaica during the next couple of days. * Formation chance through 48 hours...high...70 percent. * Formation chance through 5 days...high...80 percent.

I thought you were exaggerating for comic effect but by golly I think I counted 8, myself! I can trace two of them to the possible 11/3 SW Caribbean genesis, itself, (which I do think may need to be watched) with one of those becoming a cat 2 H in the Leewards.

For the 3rd-4th day in a row, the 12Z model consensus (every model actually including ensembles) has a potential Invest 96-L with a new sfc low forming in the SW Caribbean on 11/3. Most of the models keep it weak though the Icon gets it a bit stronger further NW. The 12Z GFS as usual has the wildest solution with it having a H hitting Jamaica, Cuba, Bahamas, and Daytona Beach. 18Z GFS takes the weak low that forms in the SW Caribbean on 11/3 and has a similar solution to the 12Z except that it hits Bermuda instead of Daytona Beach for the final landfall shown on the run. Taking with a gigantic grain because it is the GFS. Regardless of what the GFS shows, all models are still showing a weak low forming on 11/3 in the SW Caribbean, which would probably need to be watched as that is the most climo favored location in the entire basin in early November. I think I'll withhold comment on the 0Z GFS for now.