WxWatcher007

Just a super early nonsensical thought: even though we’re almost certainly going to see troughing, I think we’ll need to see how this looks after crossing the Antilles into the Atlantic to have a good sense of if it gets picked up and swept out to sea or left behind. Given the anomalous troughing out east this year, and the parade of waves (which I think increases odds this never touches land after the Antilles) I think this will be complicated for a while.

It’s beautiful here. Love it.

Near the Windward Islands (AL90): A broad area of low pressure has formed near the Windward Islands, shower and thunderstorm activity has become better organized since yesterday. Some additional development of this system is likely and a tropical depression could form by early next week while this system moves westward to west-northwestward at 10 to 15 mph, across the Lesser Antilles and over the eastern and central Caribbean Sea. Regardless of development, heavy rainfall is possible over portions of the Windward Islands during the next couple of days. Interests in the eastern and central Caribbean should monitor the progress of this system. * Formation chance through 48 hours...medium...40 percent. * Formation chance through 7 days...medium...60 percent.

Great to see you post. Hope all is well with you and your family.

Alright folks, it's just about that time to ring the bell. After a dead period late July through most of August, right on cue the basin is alive. With a caveat. Let's start here. Despite our dead period, we've been pretty active for a Nino, which means anything near normal activity. In fact, today is the first day we go BN ACE this season according to Brian McNoldy. I only say this because now is really when the rubber needs to meet the road in determining what kind of season we have, which I'll talk about more when I do my peak season forecast. For now, though, let's take our first look around the basin in quite some time. There are five areas to watch. The basin is active in the sense that there are legitimate disturbances out there--the basin is filled with them--but the overall environment for development, and certainly high end development, remains relatively hostile. Let's go one by one. Western Atlantic Orange--WxW007 Development Odds: 60% I've been watching this one for a while now, and while it still needs a lot of work, the guidance continues to believe that this will consolidate enough over the Gulf to allow for some modest development. We all know the water in the Gulf is warm, and actually some of the warmest on the globe this year. However, I think the availability of moisture in the Gulf, and just enough of a window with lower shear will allow for development before a landfall in the western Gulf coast near the TX/Mexico border. Time is a factor. Let's see how coherent this disturbance is as it passes Florida. Invest 90L--Development Odds: 70% I am bullish on this disturbance, and I have been for a while. While there was a debate on whether the monsoon trough would even break down, the western end of the trough remained convectively active. As the MT broke apart into three distinct areas, this one remained south, which is critical because it has thus far evaded the overwhelming influence of SAL and shear. It's not great, but it's just enough IMO, a theme of this post as we look around this part of the basin. The models may be playing catch up with this one, but let's see what the trends are today. Last night's intense convective burst was helpful IMO. This is one to watch in the Antilles, because as it moves into the Caribbean if it isn't sheared we should see stronger convection as it organizes some. Long term fate is uncertain. Invests 98L & 99L--Development Odds: 50% The water vapor says it all. These two were the leaders in the clubhouse, but you have everything you need to know by my combining the two in a quick paragraph. They're too north and they're struggling in a hostile environment. 98L is about to get sandblasted by shear and SAL. While 99L looks like it has a well established LLC, it's sheared and it's only going to get worse. If I had to place bets, the NHC designates 98L eventually but it's a minimal TS at best. Meh. New Wave on the Block--Development Odds 50% Another wave is poised to exit Africa, and it is another vigorous one. With 98L and 99L likely to be sacrificial waves at the end of the day, this may pave the way for this wave (or a subsequent one) to have better development odds, provided they don't get decapitated by shear. Even then, these strong waves that are forecast to come off into September may find a more favorable environment west if the SAL and TUTT shear persists in the MDR. Some guidance is latching onto this idea, but we'll see.

Alright folks, it's just about that time to ring the bell. After a dead period late July through most of August, right on cue the basin is alive. With a caveat. Let's start here. Despite our dead period, we've been pretty active for a Nino, which means anything near normal activity. In fact, today is the first day we go BN ACE this season according to Brian McNoldy. I only say this because now is really when the rubber needs to meet the road in determining what kind of season we have, which I'll talk about more when I do my peak season forecast. For now, though, let's take our first look around the basin in quite some time. There are five areas to watch. The basin is active in the sense that there are legitimate disturbances out there--the basin is filled with them--but the overall environment for development, and certainly high end development, remains relatively hostile. Let's go one by one. Western Atlantic Orange--WxW007 Development Odds: 60% I've been watching this one for a while now, and while it still needs a lot of work, the guidance continues to believe that this will consolidate enough over the Gulf to allow for some modest development. We all know the water in the Gulf is warm, and actually some of the warmest on the globe this year. However, I think the availability of moisture in the Gulf, and just enough of a window with lower shear will allow for development before a landfall in the western Gulf coast near the TX/Mexico border. Time is a factor. Let's see how coherent this disturbance is as it passes Florida. Invest 90L--Development Odds: 70% I am bullish on this disturbance, and I have been for a while. While there was a debate on whether the monsoon trough would even break down, the western end of the trough remained convectively active. As the MT broke apart into three distinct areas, this one remained south, which is critical because it has thus far evaded the overwhelming influence of SAL and shear. It's not great, but it's just enough IMO, a theme of this post as we look around this part of the basin. The models may be playing catch up with this one, but let's see what the trends are today. Last night's intense convective burst was helpful IMO. This is one to watch in the Antilles, because as it moves into the Caribbean if it isn't sheared we should see stronger convection as it organizes some. Long term fate is uncertain. Invests 98L & 99L--Development Odds: 50% The water vapor says it all. These two were the leaders in the clubhouse, but you have everything you need to know by my combining the two in a quick paragraph. They're too north and they're struggling in a hostile environment. 98L is about to get sandblasted by shear and SAL. While 99L looks like it has a well established LLC, it's sheared and it's only going to get worse. If I had to place bets, the NHC designates 98L eventually but it's a minimal TS at best. Meh. New Wave on the Block--Development Odds 50% Another wave is poised to exit Africa, and it is another vigorous one. With 98L and 99L likely to be sacrificial waves at the end of the day, this may pave the way for this wave (or a subsequent one) to have better development odds, provided they don't get decapitated by shear. Even then, these strong waves that are forecast to come off into September may find a more favorable environment west if the SAL and TUTT shear persists in the MDR. Some guidance is latching onto this idea, but we'll see.

Also, posting for posterity because we have constant complaining from some about the NHC naming every swirl.

There’s supposed to be troughing which should allow a more NW heading eventually but everything looks complicated and messy out there. 98L should develop and I think 90L will too, but poor 99L looks to be a disappointment. It looks fine for an invest on visible, but there’s still work to do. 90L benefits tremendously from being further south with limited influence from SAL and shear.

Newly designated 90L has been the most consistently convectively active of the three MDR disturbances, and it looks to be organizing nicely this morning. I expect odds to increase. Definitely worthy of an invest tag.

No recon updates since my last post lol

Recon has crossed over Mexico and reached the Pacific. Should be closing in on Hilary shortly. Given the length of the journey I’d expect another abbreviated recon period but we’ll see.

Hurricane Hilary Discussion Number 11 NWS National Hurricane Center Miami FL EP092023 900 PM MDT Fri Aug 18 2023 Hilary's cloud pattern has not changed much since earlier today. The hurricane continues to exhibit a large 30-35 n mi wide eye with a surrounding ring of deep convection with clouds tops around -75 degrees Celsius. The latest subjective Dvorak intensity estimates from TAFB and SAB support an initial intensity of 115 kt. The next Air Force Reserve reconnaissance mission is currently en route, and it should provide a better assessment of Hilary's intensity and structure overnight. Hilary has turned north-northwestward with an initial motion estimate of 335/12 kt. The track forecast reasoning is unchanged from before. Hilary is forecast to turn northward and begin to accelerate on Saturday as it is steered by deep-layer southerly flow between a strong subtropical ridge over the south-central United States and an upper-level low off the coast of central California. The models have again trended slightly faster, and the NHC foreast has been adjusted accordingly. The NHC track forecast brings the center near the west-central coast of the Baja California Peninsula in about 36 hours, and along the northwestern coast of the peninsula in 48 hours. This is near the middle of the tightly clustered guidance envelope. Users are reminded to not focus on the exact details of the track forecast as strong winds and heavy rainfall will extend far from the center. These hazards will begin well in advance of the arrival of the center. Hilary has likely peaked in intensity, and weakening is expected to begin on Saturday as it moves over cooler SSTs. A faster rate of weakening is likely to begin by 24 hours as Hilary moves over SSTs less than 26C and the vertical wind shear begins to increase. However, Hilary is forecast to be a large hurricane when it passes near the west-central coast of the Baja Peninsula, and a tropical storm when it nears the U.S./Mexico border. The NHC intensity forecast is similar to the previous advisory, and lies close to the IVCN consensus model. KEY MESSAGES: 1. Heavy rainfall associated with Hilary will begin well in advance of the center, from the Baja California Peninsula into the Southwestern United States. Preparations for the impacts of flooding from rainfall should be completed as soon as possible, as heavy rain will increase ahead of the center on Saturday. In the Southwestern United States, flash, urban, and arroyo flooding is expected, with dangerous and locally catastrophic impacts likely. 2. Hurricane conditions are expected within portions of the hurricane warning area along the west-central coast of the Baja California Peninsula Saturday night and are possible in the Hurricane Watch area. 3. Tropical storm conditions are expected to begin on Sunday in portions of southern California where a Tropical Storm Warning is in effect. 4. Large swells generated by Hilary will affect portions of the coast of southwestern Mexico, the Baja California peninsula, and southern California over the next few days. These swells are likely to cause life-threatening surf and rip current conditions. FORECAST POSITIONS AND MAX WINDS INIT 19/0300Z 19.7N 112.7W 115 KT 130 MPH 12H 19/1200Z 21.4N 113.6W 110 KT 125 MPH 24H 20/0000Z 24.2N 114.4W 95 KT 110 MPH 36H 20/1200Z 27.6N 115.4W 80 KT 90 MPH 48H 21/0000Z 32.1N 116.8W 55 KT 65 MPH...INLAND 60H 21/1200Z 37.8N 117.8W 30 KT 35 MPH...POST-TROP/INLAND 72H 22/0000Z...DISSIPATED $$ Forecaster Brown

I didn’t think the thread had any particular slant, but wanted to share the meteorology to those following. I’m actually a little more skeptical today that this’ll be beneficial to anything other than major basins, but I really have no knowledge of what’s needed out there and how it should fall.

Not quite. SAL has been historically low until recently. Sometimes you get a double edged sword of stronger waves kicking up more dust. Climatology suggests that the SAL becomes less of an issue in September and early October when the MDR is at its peak. On Hilary, an excellent thread on the meteorology behind the rain threat. FFWs already being issued as the PRE hits Nevada.

One of the best threads yet on why a historic rainfall event is likely.

It has absolutely been too amped IMO this season, but it has accurately predicted the breakdown of the monsoon trough, and I think it’ll be right with TC genesis in the Gulf next week. I think it’s going to be really complex, but I do think something tries to come out of the western Caribbean or Gulf late next week with some kind of land threat the last week of August as a result.

For whatever reason that doesn’t work for me. Yeah—no comparison IMO. Not only is this a direct hit where Kay hooked left south of the US, the rainfall is likely going to be unprecedented in the modern record for some areas. It may not be apocalyptic in LA/San Diego, but the D3 high risk suggest that it will be catastrophic in some of those areas. The wind is a distraction, even though coastal southern California rarely sees TS winds…from a TS.

Euro, GFS, and CMC all have something trying to come out of Central America/EPAC into the basin late next week. It’s entirely irrelevant how strong those op runs strengthen something in the long range, the signal is what matters. There are a lot of moving pieces here.

Not a lot of time in the storm. Already done. No sampling of the southern half.

First VDM Product: Air Force Vortex Message (URPN12 KNHC)Corrected: This observation corrected a previous observation.Transmitted: 18th day of the month at 18:37ZAgency: United States Air Force Aircraft: Lockheed WC-130J Hercules with reg. number AF96-5300 Storm Name: HilaryStorm Number & Year: 09 in 2023 (flight in the Northeast Pacific basin)Mission Number: 1Observation Number: 08 ( See all messages of this type for this mission. )A. Time of Center Fix: 18th day of the month at 18:02:30ZB. Center Fix Coordinates: 18.16N 111.94WB. Center Fix Location: 352 statute miles (567 km) to the SSW (202°) from Cabo San Lucas, Baja California Sur, Mexico.C. Minimum Height at Standard Level: 2,664m (8,740ft) at 700mbD. Minimum Sea Level Pressure: 948mb (28.00 inHg)E. Dropsonde Surface Wind at Center: From 200° at 11kts (From the SSW at 13mph)F. Eye Character: ClosedG. Eye Shape & Diameter: Circular with a diameter of 32 nautical miles (37 statute miles)H. Estimated (by SFMR or visually) Maximum Surface Wind Inbound: 93kts (107.0mph)I. Location & Time of the Estimated Maximum Surface Wind Inbound: 18 nautical miles (21 statute miles) to the ENE (61°) of center fix at 17:57:00ZJ. Maximum Flight Level Wind Inbound: From 143° at 113kts (From the SE at 130.0mph)K. Location & Time of the Maximum Flight Level Wind Inbound: 19 nautical miles (22 statute miles) to the ENE (60°) of center fix at 17:56:30ZL. Estimated (by SFMR or visually) Maximum Surface Wind Outbound: 85kts (97.8mph)M. Location & Time of the Estimated Maximum Surface Wind Outbound: 18 nautical miles (21 statute miles) to the NW (310°) of center fix at 18:16:00ZN. Maximum Flight Level Wind Outbound: From 57° at 96kts (From the ENE at 110.5mph)O. Location & Time of the Maximum Flight Level Wind Outbound: 21 nautical miles (24 statute miles) to the NW (311°) of center fix at 18:17:00ZP. Maximum Flight Level Temp & Pressure Altitude Outside Eye: 8°C (46°F) at a pressure alt. of 3,051m (10,010ft)Q. Maximum Flight Level Temp & Pressure Altitude Inside Eye: 18°C (64°F) at a pressure alt. of 3,048m (10,000ft)R. Dewpoint Temp (collected at same location as temp inside eye): 8°C (46°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: 700mbT. Navigational Fix Accuracy: 0.02 nautical milesT. Meteorological Accuracy: 0.02 nautical milesRemarks Section: Maximum Flight Level Wind: 113kts (~ 130.0mph) which was observed 19 nautical miles (22 statute miles) to the ENE (60°) from the flight level center at 17:56:30Z