WxWatcher007

Yep—an instance here where a TC can do more good than harm.

First VDM. That high SFMR almost certainly came from a gust. Product: Air Force Vortex Message (URNT12 KNHC)Transmitted: 22nd day of the month at 6:18ZAgency: United States Air Force Aircraft: Lockheed WC-130J Hercules with reg. number AF97-5304 Tropical Depression: Nine (flight in the North Atlantic basin)Mission Number: 2Observation Number: 03 ( See all messages of this type for this mission. )A. Time of Center Fix: 22nd day of the month at 5:32:10ZB. Center Fix Coordinates: 25.62N 94.19WB. Center Fix Location: 206 statute miles (332 km) to the E (96°) from Brownsville, TX, USA.C. Minimum Height at Standard Level: 723m (2,372ft) at 925mbD. Minimum Sea Level Pressure: 1004mb (29.65 inHg) - ExtrapolatedE. Dropsonde Surface Wind at Center (Undecoded): NAF. Eye Character: Not AvailableG. Eye Shape: Not AvailableH. Estimated (by SFMR or visually) Maximum Surface Wind Inbound: 52kts (59.8mph)I. Location & Time of the Estimated Maximum Surface Wind Inbound: 58 nautical miles (67 statute miles) to the NE (41°) of center fix at 5:13:30ZJ. Maximum Flight Level Wind Inbound: From 112° at 52kts (From the ESE at 59.8mph)K. Location & Time of the Maximum Flight Level Wind Inbound: 59 nautical miles (68 statute miles) to the NE (41°) of center fix at 5:13:00ZL. Estimated (by SFMR or visually) Maximum Surface Wind Outbound: 18kts (20.7mph)M. Location & Time of the Estimated Maximum Surface Wind Outbound: 40 nautical miles (46 statute miles) to the SW (228°) of center fix at 5:44:30ZN. Maximum Flight Level Wind Outbound: From 4° at 12kts (From the N at 13.8mph)O. Location & Time of the Maximum Flight Level Wind Outbound: 48 nautical miles (55 statute miles) to the SW (228°) of center fix at 5:47:00ZP. Maximum Flight Level Temp & Pressure Altitude Outside Eye: 18°C (64°F) at a pressure alt. of 758m (2,487ft)Q. Maximum Flight Level Temp & Pressure Altitude Inside Eye: 23°C (73°F) at a pressure alt. of 760m (2,493ft)R. Dewpoint Temp (collected at same location as temp inside eye): 21°C (70°F)R. Sea Surface Temp (collected at same location as temp inside eye): Not AvailableS. Fix Determined By: Penetration, Radar, Wind, Pressure and TemperatureS. Fix Level: 925mbT. Navigational Fix Accuracy: 0.02 nautical milesT. Meteorological Accuracy: 2 nautical milesRemarks Section: Maximum Flight Level Wind: 52kts (~ 59.8mph) which was observed 59 nautical miles (68 statute miles) to the NE (41°) from the flight level center at 5:13:00Z Sea Level Pressure Extrapolation From: 925mb

We have Harold as of 2am EST WxWatcher007 Peak Season Forecast (Aug 20-Oct 20) Named Storms: 13 (4) Hurricanes: 6 (0) Major Hurricanes: 3 (0) Edit: it’s 4 TCs since Aug 20—Emily, Franklin, Gert, Harold.

1:00 AM CDT Tue Aug 22 Location: 25.8°N 94.4°W Moving: WNW at 18 mph Min pressure: 1004 mb Max sustained: 45 mph

LLC is displaced SW of the convective bursts. Lowest extrapolated pressure so far 1004.4mb at ~2,500ft. We’ll see if the first pass is enough for the NHC to upgrade.

Rain contaminated higher gusts but there are some FL and SFMR obs that look clean enough at minimal TS strength IMO. Still a lot more to sample.

It’s much better convectively organized on satellite, but that west side still looks odd to me. Recon is starting to sample so we’ll see soon.

Recon in the air now. If I’m awake I’ll post what they find. Good time to head in.

Tropical Depression Nine Discussion Number 3 NWS National Hurricane Center Miami FL AL092023 1000 PM CDT Mon Aug 21 2023 Satellite imagery indicates that the depression is becoming better organized. Deep convection has been increasing near the mid-level center, with the apparent low-level center displaced on the south side of the convective mass. The latest satellite classifications still support an intensity of 30 kt, and an Air Force Reserve Hurricane Hunter is scheduled to be in the area overnight for a more detailed look at the wind field. The depression is moving fairly quickly to the west-northwest at 16 kt on the south side of a strong mid-level ridge located over the central United States. This general motion should continue through landfall tomorrow by midday. The guidance has shifted a bit to the north on this cycle, and the NHC forecast follows the recent trends. The system should strengthen soonb through landfall over the warm Gulf waters, though its time is limited. It should be noted that the cyclone moves inland between the 12- and 24-hour points so it is possible that the system gets a little stronger than the forecast intensity values below. No noteworthy changes were required to the last NHC wind speed forecast. KEY MESSAGES: 1. Heavy rainfall from Tropical Depression Nine is expected across South Texas through early Wednesday, and may produce areas of flash and urban flooding. Across portions of northern Coahuila and northern Nuevo Leon in Mexico, flash flooding with possible landslides in mountainous terrain is expected Tuesday through Wednesday. 2. Coastal flooding is possible along the south Texas coast tonight through Tuesday evening. 3. Tropical storm conditions are expected in the warning area and are possible in the watch area beginning early Tuesday. FORECAST POSITIONS AND MAX WINDS INIT 22/0300Z 25.7N 93.3W 30 KT 35 MPH 12H 22/1200Z 26.3N 96.0W 40 KT 45 MPH 24H 23/0000Z 27.3N 99.5W 30 KT 35 MPH...INLAND 36H 23/1200Z 29.0N 103.0W 20 KT 25 MPH...POST-TROP/REMNT LOW 48H 24/0000Z...DISSIPATED $$ Forecaster Blake

Nice convective bursts happening near the apparent center, but it's hard for me to tell since we're outside of radar range and don't have visible whether this is actually organizing a core. Microwave may be a bit dated so I didn't include. Looking forward to recon later. The convective bursts may be enough to get this named at 35kts.

Everything kind of seems on track. It has organized enough to make achieving TS status more likely than not, but we haven’t seen the kind of developing inner core to suggest this significantly overperforms. That said, this is when the models suggested a little take off would occur, so I’ll be watching radar and IR to see how quickly things are moving in terms of spiral banding and a tight LLC. Interestingly, 18z SHIPS increased odds for modest RI. Not seeing any evidence of that right now. The fast movement should make this a quick hitter with beneficial rain.

Franklin now stationary per recon. We saw really significant degradation of the system today and it’ll be interesting to see if this has an impact on making it too shallow for the first trough/weakness to significantly influence the early post DR/Haiti track.

Tropical Storm Franklin Discussion Number 5 NWS National Hurricane Center Miami FL AL082023 500 PM EDT Mon Aug 21 2023 Franklin is not an especially well-organized tropical cyclone this afternoon. The NOAA reconnaissance mission has been sampling the storm for a large part of the afternoon, and found a center to the south of where the position was estimated earlier today. In addition, the winds on the southwest side of the circulation are more diffuse, and overall the circulation is a bit more elongated than what the plane found yesterday at this time. Peak 850-mb flight level winds were at 48 kt just to the northwest of the circulation, which supports an intensity between 40-45 kt after using a standard reduction. The initial intensity will remain at 45 kt for this advisory, which is also in between the higher TAFB and lower SAB intensity estimates. The tropical storm has been meandering today, and my best guess at an initial motion is a drift south of due west at 265/4 kt. Given the current elongated nature of the surface circulation, the short- term track forecast is tricky, ranging from the GFS on the east side of the guidance envelope that has a center reformation to the northeast, and the CMC and ECMWF which are on the western side of the guidance envelope. The steering currents are also poorly defined currently due to a large mid-oceanic trough in the western Atlantic disrupting the flow pattern. Mid-level ridging eventually builds in to the east of Franklin, which should ultimately induce a northward motion by 24-36 h, and then northeastward between 48-96 h, as a mid-latitude trough reinforces the weakness to the north of the storm. The track guidance has slowed down again compared to the previous cycle, prolonging the time the system will remain over the Caribbean Sea before it moves over Hispaniola. The NHC track forecast is once again slower than the previous cycle and has also been nudged a touch westward compared to the previous one, but is now a bit east of the simple and corrected consensus aids. Given Franklin's current structure, I am somewhat skeptical there will be a lot of meaningful near-term intensification, especially while moderate vertical wind shear continues to disrupt the convective structure. However, both the GFS- and ECMWF-based SHIPS guidance indicate that the shear will briefly drop under 10 kt in about 24 hours, and when combined with warm 29 C sea-surface temperatures, it still seems prudent to show some intensification before Franklin moves inland over Hispaniola. Significant land interaction over the higher terrain will then lead to weakening, which could be underdone here given the current track over some of the most mountainous terrain. After Franklin emerges into the western Atlantic, another round of southwesterly shear may slow the rate of reintensification, and the latest NHC intensity forecast is a bit more subdued than the previous one, once again electing to follow the HCCA consensus aid. Given the complex intensity factors mentioned above, this is a low confidence forecast. KEY MESSAGES: 1. Heavy rainfall from Franklin is expected across portions of Puerto Rico and Hispaniola through the middle of the week. The heavy rainfall may produce areas of flash and urban flooding as well as river rises and mudslides. Across Hispaniola, significant and potentially life-threatening flash flooding is possible Tuesday into Wednesday. 2. Franklin is expected to bring tropical storm conditions to portions of the Dominican Republic and Haiti beginning on Tuesday where Tropical Storm Warnings are in effect. FORECAST POSITIONS AND MAX WINDS INIT 21/2100Z 14.3N 70.1W 45 KT 50 MPH 12H 22/0600Z 14.3N 70.9W 45 KT 50 MPH 24H 22/1800Z 15.3N 71.3W 50 KT 60 MPH 36H 23/0600Z 17.2N 71.2W 55 KT 65 MPH 48H 23/1800Z 19.1N 70.8W 40 KT 45 MPH...INLAND 60H 24/0600Z 20.6N 70.3W 45 KT 50 MPH...OVER WATER 72H 24/1800Z 22.2N 68.7W 50 KT 60 MPH 96H 25/1800Z 23.6N 66.0W 60 KT 70 MPH 120H 26/1800Z 25.6N 65.5W 70 KT 80 MPH $$ Forecaster Papin

It still looks really unlikely for the US. I think there's a legitimate threat for Atlantic Canada though.

Franklin VDM Product: NOAA Vortex Message (URNT12 KWBC)Transmitted: 21st day of the month at 18:38ZAgency: National Oceanic and Atmospheric Administration (NOAA)Aircraft: Lockheed WP-3D Orion (Reg. Num. N43RF)Storm Name: FranklinStorm Number & Year: 08 in 2023 (flight in the North Atlantic basin)Mission Number: 2Observation Number: 03 ( See all messages of this type for this mission. )A. Time of Center Fix: 21st day of the month at 18:14:48ZB. Center Fix Coordinates: 14.28N 69.88WB. Center Fix Location: 291 statute miles (468 km) to the S (179°) from Santo Domingo, Dominican Republic.C. Minimum Height at Standard Level: 1,454m (4,770ft) at 850mbD. Minimum Sea Level Pressure: 1004mb (29.65 inHg)E. Dropsonde Surface Wind at Center: From 110° at 18kts (From the ESE at 21mph)F. Eye Character: Not AvailableG. Eye Shape: Not AvailableH. Estimated (by SFMR or visually) Maximum Surface Wind Inbound: Not AvailableI. Location & Time of the Estimated Maximum Surface Wind Inbound (Undecoded): NAJ. Maximum Flight Level Wind Inbound: From 73° at 46kts (From the ENE at 52.9mph)K. Location & Time of the Maximum Flight Level Wind Inbound: 49 nautical miles (56 statute miles) to the N (351°) of center fix at 17:59:04ZL. Estimated (by SFMR or visually) Maximum Surface Wind Outbound: Not AvailableM. Location & Time of the Estimated Maximum Surface Wind Outbound (Undecoded): NAN. Maximum Flight Level Wind Outbound: From 43° at 48kts (From the NE at 55.2mph)O. Location & Time of the Maximum Flight Level Wind Outbound: 9 nautical miles to the NW (320°) of center fix at 18:17:13ZP. Maximum Flight Level Temp & Pressure Altitude Outside Eye: 24°C (75°F) at a pressure alt. of 1,523m (4,997ft)Q. Maximum Flight Level Temp & Pressure Altitude Inside Eye: 20°C (68°F) at a pressure alt. of 1,530m (5,020ft)R. Dewpoint Temp (collected at same location as temp inside eye): 12°C (54°F)R. Sea Surface Temp (collected at same location as temp inside eye): Not AvailableS. Fix Determined By: Penetration and PressureS. Fix Level: 850mbT. Navigational Fix Accuracy: 0.01 nautical milesT. Meteorological Accuracy: 5 nautical milesRemarks Section: Maximum Flight Level Wind: 48kts (~ 55.2mph) which was observed 9 nautical miles to the NW (320°) from the flight level center at 18:17:13Z Maximum Flight Level Temp: 25°C (77°F) which was observed 32 nautical miles (37 statute miles) to the NNW (337°) from the flight level center

Recon descending into Franklin now. Should be a helpful mission for understanding structure and getting data into the guidance.

Not a bad look, but again, needs an inner core to overachieve.

Yep. Once we lost the July pattern tropical became a hell of a lot harder here.

Recon en route.

Rather than screwing up the formatting, just reposting.

It's an extremely tough sell for NE. Looks legit risky for @Hazey to Nick though.

WxWatcher007 2023 Atlantic Peak Season Forecast Finally, I have the time to share my annual thoughts on the peak of the Atlantic hurricane season. This is my fifth annual forecast and the lead up to today has seen very significant uncertainty on the tenor of the season. The season so far has actually been normal in number of storms and ACE to date, which means active for a Nino. As I write, we suddenly have a TC outbreak in the Atlantic. The switch is definitely flipping in the basin. Each year on August 20, the late Dr. William Gray and his team would ring a bell, symbolizing the start of peak season. This year, we have a historically warm basin battling a Nino that is gradually increasing in influence. What does the August 20 - October 20 period hold? Here's my forecast. Peak Season Forecast (Aug 20-Oct 20) Named Storms: 13 Hurricanes: 6 Major Hurricanes: 3 Emily, Franklin, and Gert became named storms yesterday. Had I posted on the 20th, I would have forecast Emily and Franklin to develop, but not Gert. As a result, my verification will include that. The forecast also predicts PTC 9 and Invest 92L to become NS. That's already pretty active. With the current outbreak, I think the risk of a below normal season has diminished. I expect this active window to be confined to the next 4 weeks, with a sharp drop off in activity by September 20. That doesn't mean we can't/won't have NS/H/MH during the late period, but I think at that point, the evolving MJO and Nino will start closing things down. Over the past four seasons, I've done well with my forecasts. I view being within +/- 1 as a success, with points off the greater the error. I earned a B+ in 2019, A- in 2020, a disappointing C in 2021, and a rebounding B- in 2022. As a reminder, the historical average is 14/7/3. With this peak season forecast I am now forecasting an overall 18/7/3 with more NS than normal, a normal hurricane number, and normal MH number due to decreasing shear during the peak and the exceptionally warm basin even in the central Atlantic. I see ACE around normal. 1. ENSO After a three year Nina, we're solidly in an El Nino regime. Of course, every ENSO event is different, and intensity/location matters a lot. Given what I project (and I will admit I am not as good with the intensity/location stuff) and what I've seen so far, the fundamental atmospheric response in the Atlantic that allows for anomalously high shear through the basin has not yet occurred, despite the shear in the basin currently. During the peak guidance actually shows a decrease in shear, but the influence of the Nino should eventually increase, bringing a wind down of activity around the basin (particularly the Caribbean) approximately four weeks from now. 2. West African Monsoon The WAM has shown mixed signals so far this season, but now that we're entering the peak it is ramping up. We've seen numerous strong African Easterly Waves (AEWs) that have rolled off Africa, and if the GFS Ensembles are to be believed, it should continue through at least early September. With CV season coming, this is essential to the forecast, even if the MDR remains somewhat hostile with subsidence because it provides a launching point for strong waves to survive the trek into the western Atlantic where there may be more favorable conditions depending on shear. 3. Wind Shear For the most part, shear has been the opposite of what you'd expect for a Nino. Recently it has gotten much worse, but that hasn't stopped development across the basin. It has, however, limited intensity potential, which is part of the reason why I am not interested in going above normal on H or MH numbers. I do think we're going to continue having issues with TUTTs, but I don't anticipate the incredibly consistent wave breaking we saw last year that really capped potential in the basin. There is fairly high confidence in this, given the agreement by the ensembles and the seasonal trend thus far. Eventually I think the Nino will take over, but not until the damage has been done. 4. SST Anomalies/OHC If we didn't have the extraordinary SST anomalies and OHC dominating the basin, this would undoubtably be a BN season. This has really allowed for the early MDR NS, marginal activity in the basin in the face of shear/dry air, and for Don to become our first hurricane in July. It is historic warmth, and while SSTs are not the piece that drives a season, they are an essential piece. 5. SAL & Stability The check on the season so far hasn't been shear, it has been SAL and stability. After being historically low earlier in the season, SAL came back with a vengeance in July and August, stabilizing much of the basin and completely closing down even cloud development in the MDR. In fact, vertical instability has been well below climo all year in the tropical Atlantic. Times are changing though. SAL is on the decline as we reach the peak of the season, as is usually the case. The sacrificial waves, which all became named storms along the monsoon trough, has dramatically decreased SAL and moistened the environment around the basin, further increasing confidence in an active month ahead. I can't embed the gif, but the link is below. https://tropic.ssec.wisc.edu/real-time/sal/g16split/movies/goes16split.html 5. CCKW/MJO Finally, although we can't see very far, we do also have another factor making an active month more likely. It looks like we are getting favorable passage of a CCKW and the MJO looks to be on the side of Atlantic activity for the next few weeks. This should continue to promote vigorous waves. Not all will develop, but it should keep moistening the MDR and allow for waves to get further west. Overall I didn't want to go big, because we still don't know how much shear and stability will truly subside in the coming weeks. Honestly, before this week I was leaning BN overall. With the current state of the Atlantic however and a more favorable period coming aside from the annual start of the climatological peak, I do believe we see an active period that gets us to near normal before a decline after September 20 and an abrupt end by October 20. I do think that we see a lot of named storms, but because I am hedging a little more conservative I think we have fewer hurricane chances of those NS. That said, the ones that do become hurricanes will have a chance to become majors, leaving me to predict that 3 of the 6 hurricanes I project developing become majors. Final Note--Landfall Odds The past three years have seen high end storms landfall in the US, and I don't think that changes this year. With higher activity comes a greater statistical chance of a US landfall, and I do believe we have a fourth consecutive year with a major hurricane landfall in the continental United States. We'll see what happens. Happy tracking.

We're talking and doing the analysis of course, but I still think we're not going to have a good sense of this one until it gets into the SW Atlantic. Also interesting to note that with greater ridging across the Atlantic, this run of the GFS takes 92L across the basin and off the Bahamas in about 10 days. Even forces it SW. If the ridging is really coming on like that, that's interesting.

I still think this is a Maritime Canada/OTS risk. Maybe 55% Canada/45% OTS. Just not seeing the cutoff troughing we need on the models, and every mile east after DR/Haiti makes it less likely it ever hooks back west enough for NE IMO. I'd want to see smoothing of that hook north of the Antilles as the first step to even be in the game.