SnowGoose69 Posted July 31 Just now, TheDreamTraveler said: I can guarantee you if Isaias was a better put together system with a decent core moving directly over Hispaniola that it would have weakened right now instead of strengthen. The fact it was a large broad disorganized mess and moving at 18mph also helped I think. There's probably a bit more at play here too. Hispaniola can be tricky with weaker storms and how exactly they travel through the island It was also moving somewhat fast. Most of the bigger storms in late August or September or that reach there aren’t moving that quickly Quote Share this post Link to post Share on other sites
TheDreamTraveler Posted July 31 Just now, SnowGoose69 said: It was also moving somewhat fast. Most of the bigger storms in late August or September or that reach there aren’t moving that quickly Yeah 18mph is pretty fast. Right before the approach it was moving at 23mph which is extremely fast. Quote Share this post Link to post Share on other sites
WxWatcher007 Posted July 31 First VDM has no mention of eyewall structure Product: Air Force Vortex Message (URNT12 KNHC) Transmitted: 31st day of the month at 3:51Z Agency: United States Air Force Aircraft: Lockheed WC-130J Hercules with reg. number AF99-5309 Storm Number & Year: 09 in 2020 Storm Name: Isaias (flight in the North Atlantic basin) Mission Number: 5 Observation Number: 06 ( See all messages of this type for this mission. ) A. Time of Center Fix: 31st day of the month at 3:31:20Z B. Center Fix Coordinates: 20.28N 72.07W B. Center Fix Location: 102 statute miles (164 km) to the SW (216°) from Cockburn Town, Turks and Caicos Islands (U.K.). C. Minimum Height at Standard Level: 1,406m (4,613ft) at 850mb D. Minimum Sea Level Pressure: 997mb (29.44 inHg) E. Dropsonde Surface Wind at Center: From 350° at 11kts (From the N at 13mph) F. Eye Character: Not Available G. Eye Shape: Not Available H. Estimated (by SFMR or visually) Maximum Surface Wind Inbound: 65kts (74.8mph) I. Location & Time of the Estimated Maximum Surface Wind Inbound: 31 nautical miles (36 statute miles) to the ENE (63°) of center fix at 3:16:00Z J. Maximum Flight Level Wind Inbound: From 91° at 87kts (From the E at 100.1mph) K. Location & Time of the Maximum Flight Level Wind Inbound: 22 nautical miles (25 statute miles) to the NE (49°) of center fix at 3:18:30Z L. Estimated (by SFMR or visually) Maximum Surface Wind Outbound: 60kts (69.0mph) M. Location & Time of the Estimated Maximum Surface Wind Outbound: 37 nautical miles (43 statute miles) to the NW (319°) of center fix at 3:42:30Z N. Maximum Flight Level Wind Outbound: From 47° at 69kts (From the NE at 79.4mph) O. Location & Time of the Maximum Flight Level Wind Outbound: 7 nautical miles to the NW (323°) of center fix at 3:34:00Z P. Maximum Flight Level Temp & Pressure Altitude Outside Eye: 20°C (68°F) at a pressure alt. of 1,523m (4,997ft) Q. Maximum Flight Level Temp & Pressure Altitude Inside Eye: 22°C (72°F) at a pressure alt. of 1,523m (4,997ft) R. Dewpoint Temp (collected at same location as temp inside eye): 15°C (59°F) R. Sea Surface Temp (collected at same location as temp inside eye): Not Available S. Fix Determined By: Penetration, Wind, Pressure and Temperature S. Fix Level: 850mb T. Navigational Fix Accuracy: 0.02 nautical miles T. Meteorological Accuracy: 1 nautical mile Remarks Section: Maximum Flight Level Wind: 87kts (~ 100.1mph) which was observed 22 nautical miles (25 statute miles) to the NE (49°) from the flight level center at 3:18:30Z Quote Share this post Link to post Share on other sites
Kevin Reilly Posted July 31 5 minutes ago, Jackstraw said: Lol, I watched Gustav in 2008 slam head on from the S into 10k ft mountains on DR's bottom crab claw, not much stronger than this one. Only to come out the other side, re-consolidate an LLC, move back SW and hit Cuba as a Cat4. Blew my mind. I respect the shredder but it's definitely not always the death machine to TC's people make it out to be lol. May be wrong but didn’t Mathew 2018 tangle with the mountains of Cuba and redevelop a center on the north coast of Cuba? Quote Share this post Link to post Share on other sites
RU848789 Posted July 31 Yeah, I was just about to post no real change at 11 pm and saw the purple "update" lettering on the NHC site, which always means breaking news. The 11 pm advisory said 60 mph winds and then the 11:40 pm update, with hurricane hunter info, has winds at 80 mph. Think they might need to redo their track/intensity projections, which looked identical to 5 pm - they said a special advisory will be issued shortly... https://www.nhc.noaa.gov/text/refresh/MIATCUAT4+shtml/310340.shtml? Hurricane Isaias Tropical Cyclone Update NWS National Hurricane Center Miami FL AL092020 1140 PM EDT Thu Jul 30 2020 ...AIR FORCE HURRICANE HUNTER FINDS ISAIAS IS A HURRICANE... Air Force Reserve Hurricane Hunter aircraft data indicate that the tropical storm has strengthened to a hurricane. The maximum winds are estimated to be 80 mph (130 km/h) with higher gusts. The government of the Bahamas has issued a Hurricane Warning for the central and southeastern Bahamas. A special advisory will be issued shortly. SUMMARY OF 1140 PM EDT...0340 UTC...INFORMATION ---------------------------------------------- LOCATION...20.3N 72.1W ABOUT 70 MI... 110 KM ESE OF GREAT INAGUA ISLAND MAXIMUM SUSTAINED WINDS...80 MPH...130 KM/H PRESENT MOVEMENT...NW OR 305 DEGREES AT 18 MPH...30 KM/H MINIMUM CENTRAL PRESSURE...995 MB...29.38 INCHES Quote Share this post Link to post Share on other sites
turtlehurricane Posted July 31 This is absolutely unprecedented. We now have a hurricane, with a rapidly expanding and intense CDO, with all of the hot water along the full length of the Bahamas to go over before nearing Florida. There has never been a storm in my life that hit Hispaniola, and strengthened, nor a storm that just got off Hispaniola and is already intensifying and well organized. This situation just became a lot more serious, wherever it may go. 4 1 6 Quote Share this post Link to post Share on other sites
cheese007 Posted July 31 Wild how this thing has been consistently outperforming intensity forecasts despite environment and structure. Here's hoping it ends up OTS 1 Quote Share this post Link to post Share on other sites
larrye Posted July 31 2 minutes ago, turtlehurricane said: This is absolutely unprecedented. We now have a hurricane, with a rapidly expanding and intense CDO, with all of the hot water along the full length of the Bahamas to go over before nearing Florida. There has never been a storm in my life that hit Hispaniola, and strengthened, nor a storm that just got off Hispaniola and is already intensifying and well organized. This situation just became a lot more serious, wherever it may go. What of the southwesterly shear that is forecast to interact with Isaias over the next couple of days? 1 Quote Share this post Link to post Share on other sites
dmillz25 Posted July 31 As a Dominican please stop calling the island hispanola. Anyways the island helped make isaias into a hurricane 3 1 1 Quote Share this post Link to post Share on other sites
hawkeye_wx Posted July 31 It'll be interesting to see what it can do with the small core tonight. The sudden upgrade is due to the new ball of intense convection over the center, but the pressure is still 996/997 mb, which is typically not cane worthy, and there isn't much surrounding the central blob. The blob will have to persist to solidify cane status. Quote Share this post Link to post Share on other sites
turtlehurricane Posted July 31 It is also significantly more south and west than previously estimated. This is why recon is so important. This makes a Florida landfall more likely. Excited for the model runs tomorrow morning, now that we have a real center fix 1 1 Quote Share this post Link to post Share on other sites
WxWatcher007 Posted July 31 2 minutes ago, dmillz25 said: As a Dominican please stop calling the island hispanola. Anyways the island helped make isaias into a hurricane Sorry. Thanks for saying something. 1 minute ago, hawkeye_wx said: It'll be interesting to see what it can do with the small core tonight. The sudden upgrade is due to the new ball of intense convection over the center, but the pressure is still 996/997 mb, which is typically not cane worthy. The blob will have to persist to solidify cane status. One interesting thing is that even without much convection, the wind field to the west is robust as well. 1 Quote Share this post Link to post Share on other sites
purduewx80 Posted July 31 5 minutes ago, dmillz25 said: As a Dominican please stop calling the island hispanola. Anyways the island helped make isaias into a hurricane What should we call it? Quote Share this post Link to post Share on other sites
SnoSki14 Posted July 31 2 minutes ago, turtlehurricane said: It is also significantly more south and west than previously estimated. This is why recon is so important. This makes a Florida landfall more likely. Excited for the model runs tomorrow morning, now that we have a real center fix Equally a stronger system will be further east. I actually like the latest GFS run, not a bad depiction of intensity & track. Quote Share this post Link to post Share on other sites
turtlehurricane Posted July 31 Actually, it depends. If a hurricane becomes strong enough it can make its own ridging to the north via large-scale outflow subsidence, and go further west. It just depends if there's really a well-defined trough. If there is a well-defined trough, then a stronger storm is steered to the north by the upper level winds. Basically, it can go either way. This time of year a stronger system may be favored to go further west due to a lack of strong mid-latitude troughs. But we will see. Model runs tomorrow morning will help clarify, and I think by 11 am we will have a good handle on the track. Quote Share this post Link to post Share on other sites
yoda Posted July 31 Nothing really new in the updated midnight disco from Blake Hurricane Isaias Special Discussion Number 12 NWS National Hurricane Center Miami FL AL092020 1200 AM EDT Fri Jul 31 2020 An Air Force Reserve Hurricane Hunter found that Isaias has become a hurricane. Maximum flight-level winds so far were 87 kt at 850 mb, with believable SFMR values of at least 65 kt. A blend of these values gives an initial wind speed of 70 kt. Some further strengthening is likely over the next 24 hours before increasing southwesterly shear could weaken the system. The intensity forecast is modified upward from 5-10 kt through 48 hours and unchanged after that time. There are no changes to the previous track forecast. Key Messages: 1. Isaias will produce heavy rains and potentially life-threatening flash flooding and mudslides across the Dominican Republic, northern Haiti, Turks and Caicos, and the Bahamas. 2. Hurricane conditions and dangerous storm surge are expected in portions of the southeastern Bahamas overnight, central and northwestern Bahamas late Friday and Saturday, and Hurricane Warnings are in effect for these areas. Preparations to protect life and property should be rushed to completion. 3. Tropical storm conditions are possible along portions of the Florida east coast beginning Saturday, and a Tropical Storm Watch is in effect. While storm surge watches are not currently needed for this area, they may be required on Friday if the forecast track shifts closer to the coast. Heavy rains associated with Isaias may begin to affect South Florida and east-Central Florida beginning late Friday night, potentially resulting in isolated flash and urban flooding, especially in low-lying and poorly drained areas. 4. There is a risk of impacts from winds, heavy rainfall, and storm surge late this weekend from the northeastern Florida coast and spreading northward along the remainder of the U.S. east coast through early next week. The details of the track and intensity forecast remain uncertain, and it is too soon to determine the magnitude and location of these potential impacts, but interests along the entire U.S. east coast should monitor the progress of Isaias and updates to the forecast. FORECAST POSITIONS AND MAX WINDS INIT 31/0400Z 20.4N 72.2W 70 KT 80 MPH 12H 31/1200Z 21.6N 73.9W 70 KT 80 MPH 24H 01/0000Z 23.5N 76.1W 75 KT 85 MPH 36H 01/1200Z 25.2N 77.8W 75 KT 85 MPH 48H 02/0000Z 26.7N 79.0W 70 KT 80 MPH 60H 02/1200Z 28.3N 79.6W 65 KT 75 MPH 72H 03/0000Z 30.0N 79.5W 65 KT 75 MPH 96H 04/0000Z 34.6N 76.8W 65 KT 75 MPH 120H 05/0000Z 42.0N 69.0W 60 KT 70 MPH $$ Forecaster Blake Quote Share this post Link to post Share on other sites
Kevin Reilly Posted July 31 10 minutes ago, hawkeye_wx said: It'll be interesting to see what it can do with the small core tonight. The sudden upgrade is due to the new ball of intense convection over the center, but the pressure is still 996/997 mb, which is typically not cane worthy, and there isn't much surrounding the central blob. The blob will have to persist to solidify cane status. A smaller system has a much better shot to develop fast compared to a larger circulation. This could really ramp up as small compact system as it cruises through the Bahamas. Shear will likely increase as the trough approaches which will make this system area wise grow and ventilatate the system north bound as it approaches Florida. I think the best window for developing now and for the next 36-48 hours after that not so much While forced up the east coast. 1 Quote Share this post Link to post Share on other sites
Tatamy Posted July 31 Weather Radar from the Bahamas https://www.accuweather.com/en/bs/georgetown/28155/weather-radar/28155 Quote Share this post Link to post Share on other sites
WinterWolf Posted July 31 6 minutes ago, turtlehurricane said: Actually, it depends. If a hurricane becomes strong enough it can make its own ridging to the north via large-scale outflow subsidence, and go further west. It just depends if there's really a well-defined trough. If there is a well-defined trough, then a stronger storm is steered to the north by the upper level winds. Basically, it can go either way. This time of year a stronger system may be favored to go further west due to a lack of strong mid-latitude troughs. But we will see. Model runs tomorrow morning will help clarify, and I think by 11 am we will have a good handle on the track. NHC still saying southwesterly shear could weaken this system after 24 hrs. Be very interesting to see if that actually takes place or not? 1 Quote Share this post Link to post Share on other sites
Kevin Reilly Posted July 31 3 minutes ago, Tatamy said: Weather Radar from the Bahamas https://www.accuweather.com/en/bs/georgetown/28155/weather-radar/28155 Wow he’s a tiny little thing from what it was that huge mess and winds extending 415 miles this morning just an amazing transformation in less than 24 hours. I’ve never seen that dramatic of a change. Quote Share this post Link to post Share on other sites
dmillz25 Posted July 31 12 minutes ago, purduewx80 said: What should we call it? I understand that’s the name of the entire island. But tbh its divided by 2 countries, the DR and Haiti, I just feel like the countries should be named separately. 2 1 Quote Share this post Link to post Share on other sites
Will - Rutgers Posted July 31 12 minutes ago, yoda said: FORECAST POSITIONS AND MAX WINDS INIT 31/0400Z 20.4N 72.2W 70 KT 80 MPH 12H 31/1200Z 21.6N 73.9W 70 KT 80 MPH 24H 01/0000Z 23.5N 76.1W 75 KT 85 MPH 36H 01/1200Z 25.2N 77.8W 75 KT 85 MPH 48H 02/0000Z 26.7N 79.0W 70 KT 80 MPH 60H 02/1200Z 28.3N 79.6W 65 KT 75 MPH 72H 03/0000Z 30.0N 79.5W 65 KT 75 MPH 96H 04/0000Z 34.6N 76.8W 65 KT 75 MPH 120H 05/0000Z 42.0N 69.0W 60 KT 70 MPH that seems an optimistically muted intensity forecast. Quote Share this post Link to post Share on other sites
purduewx80 Posted July 31 2 minutes ago, dmillz25 said: I understand that’s the name of the entire island. But tbh its divided by 2 countries, the DR and Haiti, I just feel like the countries should be named separately. Thanks, understood! Was wondering if there was an old school Taino name to use instead. Quote Share this post Link to post Share on other sites
WinterWolf Posted July 31 2 minutes ago, Kevin Reilly said: Wow he’s a tiny little thing from what it was that huge mess and winds extending 415 miles this morning just an amazing transformation in less than 24 hours. I’ve never seen that dramatic of a change. But...will he carry all that mass along with him as he develops? Or will he be a puny lil Storm now? That’s gonna change a lot of things going forward if he gets very small...no? Quote Share this post Link to post Share on other sites
Kevin Reilly Posted July 31 Just now, WinterWolf said: But...will he carry all that mass along with him as he develops? Or will he be a puny lil Storm now? That’s gonna change a lot of things going forward if he gets very small...no? I would think so perhaps a more westerly track over time? We will know by say no tomorrow if not little sooner. Quote Share this post Link to post Share on other sites
Tar Heel Snow Posted July 31 33 minutes ago, WxWatcher007 said: First VDM has no mention of eyewall structure Product: Air Force Vortex Message (URNT12 KNHC) Transmitted: 31st day of the month at 3:51Z Agency: United States Air Force Aircraft: Lockheed WC-130J Hercules with reg. number AF99-5309 Storm Number & Year: 09 in 2020 Storm Name: Isaias (flight in the North Atlantic basin) Mission Number: 5 Observation Number: 06 ( See all messages of this type for this mission. ) A. Time of Center Fix: 31st day of the month at 3:31:20Z B. Center Fix Coordinates: 20.28N 72.07W B. Center Fix Location: 102 statute miles (164 km) to the SW (216°) from Cockburn Town, Turks and Caicos Islands (U.K.). C. Minimum Height at Standard Level: 1,406m (4,613ft) at 850mb D. Minimum Sea Level Pressure: 997mb (29.44 inHg) E. Dropsonde Surface Wind at Center: From 350° at 11kts (From the N at 13mph) F. Eye Character: Not Available G. Eye Shape: Not Available H. Estimated (by SFMR or visually) Maximum Surface Wind Inbound: 65kts (74.8mph) I. Location & Time of the Estimated Maximum Surface Wind Inbound: 31 nautical miles (36 statute miles) to the ENE (63°) of center fix at 3:16:00Z J. Maximum Flight Level Wind Inbound: From 91° at 87kts (From the E at 100.1mph) K. Location & Time of the Maximum Flight Level Wind Inbound: 22 nautical miles (25 statute miles) to the NE (49°) of center fix at 3:18:30Z L. Estimated (by SFMR or visually) Maximum Surface Wind Outbound: 60kts (69.0mph) M. Location & Time of the Estimated Maximum Surface Wind Outbound: 37 nautical miles (43 statute miles) to the NW (319°) of center fix at 3:42:30Z N. Maximum Flight Level Wind Outbound: From 47° at 69kts (From the NE at 79.4mph) O. Location & Time of the Maximum Flight Level Wind Outbound: 7 nautical miles to the NW (323°) of center fix at 3:34:00Z P. Maximum Flight Level Temp & Pressure Altitude Outside Eye: 20°C (68°F) at a pressure alt. of 1,523m (4,997ft) Q. Maximum Flight Level Temp & Pressure Altitude Inside Eye: 22°C (72°F) at a pressure alt. of 1,523m (4,997ft) R. Dewpoint Temp (collected at same location as temp inside eye): 15°C (59°F) R. Sea Surface Temp (collected at same location as temp inside eye): Not Available S. Fix Determined By: Penetration, Wind, Pressure and Temperature S. Fix Level: 850mb T. Navigational Fix Accuracy: 0.02 nautical miles T. Meteorological Accuracy: 1 nautical mile Remarks Section: Maximum Flight Level Wind: 87kts (~ 100.1mph) which was observed 22 nautical miles (25 statute miles) to the NE (49°) from the flight level center at 3:18:30Z Not to take away from the analysis, but some time when we’re not all focused on a storm, I’d love someone to make or link to a tutorial on how to read all these data points in updates like this. I’ll hang up and keep listening and learning. Thanks everyone! 1 Quote Share this post Link to post Share on other sites
dmillz25 Posted July 31 3 minutes ago, purduewx80 said: Thanks, understood! Was wondering if there was an old school Taino name to use instead. Ayiti was the Taino name. Seems like Isaias wants to come up this way. I wonder what was the last storm to impact the DR/Haiti and the NEUS 1 Quote Share this post Link to post Share on other sites
Orangeburgwx Posted July 31 Full rainbow on the FL winds as the plane goes for another passSent from my LML212VL using Tapatalk Quote Share this post Link to post Share on other sites
Orangeburgwx Posted July 31 Just to point out, this was dropped in the Bahamas ahead the storm...No shear, universal wind directionSent from my LML212VL using Tapatalk Quote Share this post Link to post Share on other sites
Orangeburgwx Posted July 31 The dry air however might cut it off...Sent from my LML212VL using Tapatalk Quote Share this post Link to post Share on other sites
