GaWx

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.

Meanwhile, the model consensus based on the latest runs of each model (12Z, 6Z, 0Z) continues to suggest a weak low in the SW Caribbean ~November 3rd. This is not Invest 95L. (Future 96L??) This includes the 12Z runs of the ICON, CMC, GFS, Euro, and UKMET. The GFS is another run that does a "wrong way Lenny" with it as it takes it ENE to near W PR. Take that with a huge grain, of course.

Please start the 95L thread if you think it is worthy. I personally think that the 70% chance of TD+ within 5 days for this is too high considering mostly unimpressive model consensus and think it is more like 40% as of now: ZCZC MIATWOAT ALL TTAA00 KNHC DDHHMM Tropical Weather Outlook NWS National Hurricane Center Miami FL 200 PM EDT Fri Oct 28 2022 For the North Atlantic...Caribbean Sea and the Gulf of Mexico: 1. Eastern Caribbean: A broad area of low pressure over the eastern Caribbean Sea continues to produce a large area of disorganized showers and thunderstorms extending from the Windward Islands west-northwestward for several hundred miles. Environmental conditions are forecast to be conducive for gradual development over the next few days, and a tropical depression is likely to form this weekend or early next week while the disturbance moves slowly westward or west-northwestward over the central Caribbean Sea. Regardless of development, locally heavy rainfall is possible over portions of the Lesser Antilles, the Virgin Islands, and Puerto Rico through this weekend. * Formation chance through 48 hours...low...30 percent. * Formation chance through 5 days...high...70 percent.

That's an interesting point. However, also keep in mind that none of 1954, 1915, 1908, and 1892 had a preceding strong El Nino.

After pretty much being on its own having had nearly a week's worth of runs showing almost all hurricanes at peak in the E or C Caribbean, the 12Z GFS has no more than a TD to possibly low end TS from this on the entire run! That's pretty bad imho though it was fortunately pretty predictable due to doing this kind of thing on its own at times in the past. And now this run could turn out to be too weak! Edit: The 12Z EPS retains the idea of a possible 2nd TC (if the initial Car mandarin low actually has TCG) in or near the SW Caribbean in early November. Edit: Regarding the "mandarined" low, the Happy Hour GFS more than likely is not even showing a TD with at most a weak TD for a short period. Too funny!

Regarding your linked article: 1. I don't think that the current triple dip La Nina is all that notable from a climate perspective. Per both the NOAA ONI table that goes back to 1950 and Eric Webb's ENSO SSTA table that goes back earlier, there were these triple dipping cold ENSO periods: A) 1892-3, 93-4, 94-5 B)1908-9, 09-10, 10-1 C) 1915-6, 16-7, 17-8 D) ASO of 1954, OND of 55, JAS of 56 E) 1973-4, 74-5, 75-6 F) 1983-4, 84-5, 85-6 G) 1998-9, 1999-2000, 2000-1 H) 2020-1, 21-2, 22-3 So, other than the longer period between the triple dips of the 1910s and 1950s, these have occurred 7-22 years apart since the late 1800s. The current one started 22 years after the start of the prior one. So, I don't see it being that notable that we're now in a triple dip as it was kind of due. 2. The same article refers to a cooling trend between 1979 and 2020 in much of the E Pacific off of S.A. Well, 2020 was the start of the current triple dip La Niña. And 1979 was going into a weak El Niño. So, if this is merely based on the difference between 1979 and 2020, then obviously it was notably cooler in 2020 than in 1979 off of S.A. That isn't due to a longer term trend but rather due to a short term cooling in 2020 due to La Niña as the image below shows. What if the ending point had been during the super El Niño of 2015 instead of 2020? The trend from 1979 off of S.A. would have been warmer rather than cooler. https://www.webberweather.com/ensemble-oceanic-nino-index.html https://origin.cpc.ncep.noaa.gov/products/analysis_monitoring/ensostuff/ONI_v5.php

In addition to the potential that this first TC forms in the central Caribbean in a few days, the model consensus is suggesting that a 2nd TC may form in or near the SW Caribbean during the first few days of November. That includes the 0Z UKMET and yesterday's 12Z UKMET in addition to other models like the Euro, ICON, and GFS. The EPS, GEFS, and GEPS also are suggesting this has a good chance to occur. So, as crazy as it sounds, don't be surprised if we get both Lisa and Martin form in the Caribbean next week.

The 12Z Euro has a weak closed low form in the C Car, the first run doing that. Prior runs have had no more than a very weak low and that in the W Car. Let's see if this is the start of a trend on the Euro.

0Z GFS: no TCG until the C Car. Much more reasonable. Edit: But then it forms a 2nd one behind it in the C Car that goes east lol. I'm not counting this part as reasonable lmao.

The 12Z Euro and UKMET continue with no TCG at all. However, they both have weak lows in the SW Car day 6+ that will need to be watched for potential TCG due to more favorable conditions, considering what the 12Z CMC and ICON as well as yesterday's 12Z JMA show, noting that climo favors that area over all others, La Nina climo, and recent decades of increased activity late in the season: Oct 21-31 geneses: (add two more to this in the W Car for 2016-21) Nov 1-10 geneses:

For some reason, Tidbits doesn't have either the 0Z or 6Z GFS. But I later found them at Pivotal and Weathernerds. I have a lot of doubt that the GFS, ICON, and CMC are actually developing the same wave. What do others think? Based on what it has done many times in the recent past (~25 runs in a row in mid May in the W Car for example that turned out to be nothing), I still think the GFS is drunk with its E Car TCG into a H while still in the E Car. I'm also considering climo as well as the Euro and UKMET not having an E Car TCG. Looking closely at the 0Z UKMET maps, all it has is a very weak low (1012 mb) at the ABC Islands (12N, 69W) at hour 84 (a far different scenario vs the GFS) that then moves westward with no TCG into the far SW Car. It finally develops some in the far SW Car while still moving westward and ends up at 1007 mb at hour 168 near 11N, 82W (150 miles E of the Nicaragua/Costa Rica border). I'm still sticking with a C or W Car TCG, if there is any, by early to mid next week and expect no more than a weak low in the E Car preceding that possibility later this week that moves westward just N of SA.

Sound familiar? Back in mid May, there were something like 25 GFS runs in a row with W Caribbean TCG that lead to modeled H landfalls in many cases while other models were mainly quiet. Then about a week after the first run with it, the GFS dropped it and never was heard from about this timeframe again. I think that's likely what's happening now with its E Car TCG. I suspect it will at some point throw in the towel on E Car TCG. Perhaps then it will change to a much more reasonable C or W Car TCG. Even the 0Z CMC has TCG in the C Car.

The 0Z CMC with its CCar TCG is a much more believable scenario vs the GFS SECar TCG. I don't see the 0Z GFS on Tidbits. Where did you see it?

Maybe so/we'll see or maybe it has also been sniffing something. Can anyone recall the last time the GFS with some support from the ICON sniffed out something in the Caribbean like this? We can follow the wave whose vorticity the GFS is focusing on as it is centered near 9-10 N, 51W.

I think that the GFS has been smoking the crack pipe for days, but now we can add Happy Hour's effects to the mix.

Regarding the now cherry nearing Bermuda, aka Invest 94L, the Euro/UKMET/GFS takes the LLC to the Cape Cod to Maine corridor Wednesday. Here's the relevant part of the TWO that indicates it is now likely to be designated a TD shortly: Central Subtropical Atlantic: Satellite and Bermuda radar images indicate that the low pressure system located about 100 miles east-southeast of Bermuda now has a well-defined center and is producing a relatively concentrated area of showers and thunderstorms. If the thunderstorm activity persists near the center, the disturbance will likely become a tropical depression later today or tonight while it moves west-northwestward and passes near Bermuda. After that time, the system is expected to turn northward and move toward cooler waters and into a region of unfavorable upper-level winds, which should limit additional development. Regardless of development, periods of locally heavy rainfall and gusty winds are expected over Bermuda through tonight. Interests in Bermuda should monitor the progress of this system. * Formation chance through 48 hours...high...70 percent. * Formation chance through 5 days...high...70 percent.

I'm wary of the GFS overdevelopment bias this season in the southern Caribbean off of South America and it could be coming into play here. The 12Z ICON doesn't have actual TCG until the C Caribbean and it isn't more than a TS as of hour 180. That's the best support the GFS has. And sometimes the ICON has overdone things this season. The 12Z CMC has only a very weak low and no TCG. The 12Z UK, Euro, and JMA have very little til a weak low in the SW Car. That's the part of the Car that I have more interest in for TCG (next week). These model wars make these forecasting threads extra fun! The GFS is developing this at least partially from vorticity located now per the model near 9N, 50W. I wonder how it is looking there right now.

Having already realized that FL as well as other areas in the W basin may very well still be at risk again before the end of the season based especially on recent La Niña climo, here's my take on this potential system fwiw: After having the two weakest runs since the 6Z 10/21 run at 12Z and 18Z yesterday and thus looking to me like it was quite possibly getting close to giving up on a H in the E Car, these last 3 (0Z, 6Z, 12Z) have been the strongest in the E Car! I still think the exclusive to GFS idea of a H in the E Car from this is out to lunch based on a combo of bias, relative lack of model support, and climo and that a TCG from this, if any, would thus wait til the C or W Caribbean, but we'll see. The GFS has done this kind of thing in the past where it would stubbornly hold onto a H run after run on its own only to later abandon it, sometimes abruptly. It is almost as if the GFS is a trolling model at times lol.

After having had the two weakest runs (yesterday's 12Z and 18Z) since the string of GFS ECar Hs started with the 6Z 10/21 run, the last two runs (0Z/6Z) have gone the opposite way to the strongest through hour 198 (12Z on 11/1)! I still think the GFS' idea of a H in the ECar is wrong and that any TCG, if there is any, would likely wait til the C or WCar. This is quite the interesting situation from a forecasting perspective with such major differences persisting among the main models! I still think the odds of one more significant land impacting TC somewhere in the W basin this season are pretty high based on recent decades of La Niña season history, especially since 2005.

And now the 0Z GFS at hour 198 has the strongest H it has had at that forecast timeframe with 970 mb S of Hispaniola.