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WxWatcher007

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  1. Ends up being slightly west and about the same intensity pressure wise.
  2. And it looks like the result is stronger and faster at least so far
  3. WxWatcher007 2021 Atlantic Hurricane Peak Season Forecast I'm a few days late due to the timing of Hurricane/Tropical Storm Henri, but it's time for me to issue my 2021 forecast for the peak of the Atlantic hurricane season. In recent years, my outlooks have done very well, and last year's historic season was my best yet. For those that haven't followed these forecasts, I look at the climatological peak of the season, from August 20 to October 20. Of course, with a few days lost we shift August a bit. Last year, we saw an active peak that pushed out a number of major hurricanes in the back end of September and into October and beyond. Peak Season Forecast Numbers (August 25-October 20) Named Storms: 13 Hurricanes: 9 Major Hurricanes: 5 The numbers above are bullish to say the least. Based on this forecast, more than 50% of the hurricanes that develop over the next two months would become majors. We'd likely rival 2005 and 2020 in the number of major hurricanes in a season should this come to pass. Let's take a look at why I am so bullish on the peak of the season. 1. ENSO First and foremost, ENSO will tell you whether you are likely to see an active season or not. After last year's La Nina, there were significant questions over whether we'd see a slide toward more neutral conditions. Officially, ENSO neutral conditions are present, but we are once again marching toward an La Nina. In fact, we are under a La Nina watch. The Nino 3.4 region in particular has slid colder since the end of June, potentially heralding a Nina regime for the peak of the season, especially in atmospheric condition reflection in October. The current neutral state of ENSO and potential for a Nina strongly suggests that an active peak of the hurricane season will present itself in 2021. It is important to note that a bona fide nina is not necessary for this forecast to verify. 2. Atlantic Multi-decadal Oscillation (AMO) What is the AMO? It's another important long term factor in determining potential during a season. A warm AMO is associated with periods of higher activity. We've been in this state for quite some time (hence AMO), and that looks to continue. Combined with the other factors as you will see, it favors activity. The AMO facilitates 1) a wetter West African Monsoon and more robust wave activity, 2) warmer SSTs in the Main Development Region (MDR), and 3) lower vertical wind shear. 3. Sea Surface Temperatures (SSTs) and Tropical Cyclone Heat Potential (TCHP) The thermal environment over the Atlantic basin is mixed. First, let's talk SSTs. While they're warm in an absolute sense, from an anomaly standpoint, they're not that impressive. I think that the relatively lukewarm waters will reduce the potential of an extremely high named storm peak season. I expect a well above average number of named storms as the SSTs are more or less on par with the last 5 years of SSTs, each of which produced above average hurricane seasons. However, as you will see below, SSTs fall well short of the extraordinary warmth we saw in 2020. I believe that will have an impact on the length of the season post October 20 and the number of named storms (think marginal systems) as we progress into the latter part of the peak. On the other hand, what the 2021 basin lacks in quantity it makes up for in quality. This is a very high TCHP environment. As a refresher, TCHP is essential to the development of major hurricanes as it provides systems with deep reservoirs of oceanic heat that allows for the high end intensification of hurricanes. As you will see below, the TCHP of 2020 was off the charts, but the extent and depth of high TCHP waters in 2021 is greater than all of the other recent active seasons that had significant numbers of major hurricanes, and just as important, the high TCHP levels are in regions that coincide where I believe storms will be focused this peak--the Caribbean, Gulf, and SE coast. As a result, what we may lose in named storms in the subtropics and MDR we could make up for in hurricanes and major hurricanes. We're already starting to see this come into greater focus with the current disturbance in the Caribbean and to a lesser extent with Elsa, Fred, Grace, and Henri, three of which became hurricanes. 3. Wind Shear Let's refer back to ENSO here. One of the biggest reasons neutral to Nina seasons feature higher Atlantic activity is the drop in wind shear that comes with the ENSO state. Here's the shear departures in a weak Nino, which we are not expecting. Above, the Caribbean is effectively closed for business. That reduces major hurricane potential. Here's a warm neutral, which again, we are not expecting. Here you see less wind shear near the coast, and less shear in the MDR, including the Caribbean. So what do we have this season? With a cool neutral regime that could become a Nina, we have shear that favors an above average season. Once again, the reduced shear is present in places where TCHP is best and more storms are likely to form, and while it may look higher in the Caribbean, there can be sizable differences between an eastern Caribbean (i.e. graveyard) system environment and a western Caribbean system environment. The shear profiles strongly favor the development of more hurricanes and major hurricanes IMO, especially as we reach the climatological nadir of shear in September and October. 4. MJO/CCKW Timing The fourth and final factor I'm looking at in a significant way this season is more a stroke of luck (good or bad depending on your perspective). We have an MJO and CCKW regime which will enhance activity in September and likely October. First, the MJO. Let's look at the CFS. This is a HUGE signal for an active Atlantic. Eric Webb explains it much better than I could ever hope to, but essentially this phase of the MJO in September is prime for AEW (wave) activity through the month and again, even if those waves don't immediately develop they are likely to find more favorable thermodynamic, moisture, and wind shear environments. Now that I've tried, here's Eric: The active period of the MJO is timed perfectly with the peak of the hurricane season. That means plenty of activity. To hammer home the point, here's Phase 4. Image once again courtesy of Eric Webb. NW Caribbean, Gulf, central/eastern MDR, and SE coast. Homebrew galore. So with each of these factors at play I expect a very active peak that has a high level of named storms (though not historically high), hurricanes, and a potentially historic number of major hurricanes. Unlike last season, that had a distribution of high end hurricanes later in the peak (and after lol), I expect high end storms to be distributed throughout the peak, in large part due to the MJO and well-timed CCKWs that provide a boost to waves that are unable to develop in the Atlantic portion of the MDR but find a more favorable environment in the Caribbean and perhaps off the SE Coast. My margin for error as it is every year is +/- 1 storm in each category. Final Note-Landfall Odds Last year was historic in the landfall department, with 11 named storms (6 hurricanes/5 tropical storms) making landfall along the US coast. The overwhelming majority made landfall in the Gulf. One hurricane made landfall along the East Coast, Isaias, along the coast of NC. This season has already seen 5 US landfalls--Claudette, Danny, Elsa, Fred, and Henri--all tropical storms. Although the pattern over the next few weeks may favor recurves of CV waves (as the pattern usually does--few CVs actually develop in the central/eastern MDR and make it to the US), with anomalous ridging favored through the peak and the potential for Caribbean and SE coast homebrew in September and October, I believe we are on the path toward another high to potentially historic landfall season. For now, the Gulf is favored, but the East Coast cannot let its guard down, especially in late September and October when climo favors SE coast and Caribbean homebrew and troughing in the east. We'll see what happens. I do not think there will be a shortage of threats. Hope you enjoyed reading.
  4. It looks quite good for a disturbance. Everyone knows it's coming, just look at the wording of the outlooks. It's crazy strong for an invest. 1. A broad area of low pressure is expected to form over the western Caribbean Sea during the next day or so from a tropical wave currently located north of Colombia. Environmental conditions are forecast to be conducive for development, and a tropical depression or tropical storm is likely to form late this week or over the weekend. The system is expected to move northwestward over the northwestern Caribbean Sea and near or across the Yucatan Peninsula of Mexico on Friday and into the Gulf of Mexico this weekend, where conditions are expected to be favorable for additional development. Regardless of development, heavy rainfall and flooding will be possible through the weekend in portions of Central America and the Yucatan Peninsula. In addition, this system could bring dangerous impacts from storm surge, wind, and heavy rainfall to portions of the coasts of Louisiana, Texas, and the Mexican state of Tamaulipas late this weekend and early next week. However, uncertainty remains large since the system has yet to form. Interests in these areas should closely monitor the progress of this system and ensure they have their hurricane plan in place. An Air Force Reserve reconnaissance aircraft is scheduled to investigate the system Thursday afternoon, if necessary. * Formation chance through 48 hours...medium...60 percent. * Formation chance through 5 days...high...80 percent.
  5. This x100. Recon is scheduled to be out there tomorrow and as we’ve seen with our last few systems, that low level and high level/environmental data will be key in helping the guidance pinpoint the landfall envelope and hopefully intensity as well.
  6. I understand there’s a drought that needs busting down there.
  7. 97L was designated as having a high chance of development earlier today by the NHC, with 70% odds of development in 5 days. Some guidance is bullish on intensification chances in a few days. Tropical Weather Outlook NWS National Hurricane Center Miami FL 800 PM EDT Tue Aug 24 2021 For the North Atlantic...Caribbean Sea and the Gulf of Mexico: 2. A broad trough of low pressure is producing disorganized showers and thunderstorms over the central tropical Atlantic about 1000 miles east-northeast of the northern Leeward Islands. Little development of this system is expected during the next day or two due to unfavorable upper-level winds. Afterwards, environmental conditions are expected to become more conducive for development, and a tropical depression is likely to form by the end of the week while the system turns eastward over the central Atlantic. * Formation chance through 48 hours...low...20 percent. * Formation chance through 5 days...high...70 percent.
  8. Peak season is approaching and it's looking like it in the Atlantic, with three named systems (Fred, Grace, Henri) recently and more likely coming in the next week. Invest 99L was designated today by the NHC and although it only has 60% 5 day odds, the guidance in totality has a very strong signal for TC genesis, and more concerning, a very conducive environment for development in the Gulf should the system organize sufficiently. Let's begin a more targeted discussion. Tropical Weather Outlook NWS National Hurricane Center Miami FL 800 PM EDT Tue Aug 24 2021 For the North Atlantic...Caribbean Sea and the Gulf of Mexico: 1. A broad area of low pressure is expected to form over the southwestern Caribbean Sea in a couple of days from a tropical wave currently located over the central Caribbean Sea. Environmental conditions are forecast to be conducive for development of the low if it remains over water, and a tropical depression could form late this week or this weekend while the system moves northwestward over the northwestern Caribbean Sea, across the Yucatan Peninsula of Mexico, and into the southwestern Gulf of Mexico by Sunday. * Formation chance through 48 hours...low...20 percent. * Formation chance through 5 days...medium...60 percent.
  9. It’s not over lol. Patterns reshuffle. The general look September and October will probably feature a return to the ridging that allows for some CVs to get further west. Yeah. I think there will be a little more MDR activity than last year because of the favorable MJO and eastern MDR environment which favors more instability IMO (despite SSTs), but I think when climo shifts to the homebrew regions in late September/early October it’ll be red hot.
  10. Not much sleep to be had through most of October.
  11. I think we get one more threat, but that’s all speculation. I do believe some of the models showing anomalous SE Canada ridging which obviously was just critical to our landfall. Unsurprisingly, there’s a greater chance of impact in the US there are more TCs, and I don’t think numbers will be an issue this year, even with a cooler MDR than some recent years.
  12. Henri delayed it, but soon I’m going to get my annual peak season forecast out (Aug 20-Oct 20). I’m as bullish as I’ve ever been which is nuts because the last few seasons have had extraordinarily hot peaks.
  13. I did drive down to RI at the start of the day, but yes, the top 5 river flood was basically down the street
  14. Just following up on yesterday, it’s been really awesome to see so many reach out to inquire about my content, especially in the last year. I’ve gotten so much better positioning myself and documenting wx. Years ago it was just me and an old camera but now I’m capable of doing so much more. I sometimes wish I had more time to put into it but I know I’m doing a lot already. Can’t wait to hit the road again.
  15. Radar actually looks pretty good out in western CT. Someone might get smoked today.
  16. Wow. Ten years ago I was sitting in a law school orientation when all of a sudden the ground shook. I looked at my cup of water and it was vibrating like Jurassic Park. Still surreal lol.
  17. Just responded. Thanks. No real damage. Though one of our main roads is covered and idk about the nearby homes because it was getting dark. River has come up about another half foot since that video and the flow increased by 600cfs. Wish it were daylight lol.
  18. We had two top ten floods last month and this blows them away, both in height and flow. Crazy.
  19. Top 5 river flood event taking place here in town. The river went from 3.42ft 24 hours ago to 11ft tonight. Gauge height beats 1955.
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