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Tropical Storm Beryl Discussion Number 33 NWS National Hurricane Center Miami FL AL022024 400 PM CDT Sat Jul 06 2024 Beryl's convective organization has increased since the last advisory, with a ragged band forming in the western semicircle. However, this band is best organized around what appears to be a mid-level center to the north or northeast of the low-level center. Earlier aircraft data indicated that the maximum winds were near 50 kt and the central pressure was in the 997-999 mb range, and since that time various objective intensity estimates have shown little change. Thus, the initial intensity remains 50 kt. The next aircraft missions into the cyclone should arrive around 2300-0000Z. Beryl is still being affected by shear and dry air entrainment, which helped produce a large arc cloud that was visible for most of the day to the south and southwest of the convection. The initial motion is now 310/11 kt. Water vapor imagery continues to show a developing mid-latitude trough over the central United States that is opening a break in the subtropical ridge over Texas. Beryl should move northwestward for the next 24 h or so, then gradually turn north and move into the break. This motion should lead to the cyclone making landfall on the Texas coast between 36-48 h. Recurvature to the northeast is subsequently expected after 60-72 h. There has been a little bit of a northward shift in the guidance and track, due mainly to a more northward initial position. While this has produced only a small change in the forecast landfall location, the landfall time is now a few hours earlier than in the previous advisory. It should be noted that some erratic motion could occur tonight due to possible center reformations. While Beryl remains in an area of southerly vertical shear and mid- to upper-level dry air, the convection has been persistent during the past several hours. The shear is forecast to decrease by Sunday morning, which should allow Beryl to re-intensity as shown by all of the guidance. The intensity forecast calls for Beryl to regain hurricane status Sunday or Sunday night, and to reach an intensity of around 75-kt near the time of the Texas landfall. This intensity is based on the regional hurricane models, which have landfall intensities ranging from 65-85 kt. After landfall, Beryl is expected to weaken, with the system forecast to decay to a remnant low pressure area by 96 h. It is important to note that the average NHC track error at 36 hours is about 50-60 miles and the average intensity error is close to one category. Users are reminded to consider these uncertainties when using the forecast information. FORECAST POSITIONS AND MAX WINDS INIT 06/2100Z 23.9N 93.0W 50 KT 60 MPH 12H 07/0600Z 24.8N 94.2W 55 KT 65 MPH 24H 07/1800Z 26.0N 95.5W 65 KT 75 MPH 36H 08/0600Z 27.5N 96.3W 75 KT 85 MPH 48H 08/1800Z 29.1N 96.7W 60 KT 70 MPH...INLAND 60H 09/0600Z 30.8N 96.4W 35 KT 40 MPH...INLAND 72H 09/1800Z 32.4N 95.2W 25 KT 30 MPH...INLAND 96H 10/1800Z 35.0N 91.5W 20 KT 25 MPH...POST-TROP/INLAND 120H 11/1800Z 38.0N 88.0W 20 KT 25 MPH...POST-TROP/INLAND $$ Forecaster Beven

Tropical Storm Beryl Advisory Number 33 NWS National Hurricane Center Miami FL AL022024 400 PM CDT Sat Jul 06 2024 ...HURRICANE AND STORM SURGE WARNINGS ISSUED FOR PORTIONS OF THE COAST OF TEXAS... ...HURRICANE-FORCE WINDS, LIFE-THREATENING STORM SURGE, AND HEAVY RAINS EXPECTED IN PORTIONS OF SOUTH TEXAS... SUMMARY OF 400 PM CDT...2100 UTC...INFORMATION ---------------------------------------------- LOCATION...23.9N 93.0W ABOUT 385 MI...615 KM SE OF CORPUS CHRISTI TEXAS MAXIMUM SUSTAINED WINDS...60 MPH...95 KM/H PRESENT MOVEMENT...NW OR 310 DEGREES AT 13 MPH...20 KM/H MINIMUM CENTRAL PRESSURE...997 MB...29.44 INCHES WATCHES AND WARNINGS -------------------- CHANGES WITH THIS ADVISORY: A Hurricane Warning is now in effect for the Texas coast from Baffin Bay northward to Sargent. A Tropical Storm Warning is now in effect for the Texas coast north of Sargent to High Island. A Storm Surge Warning has been issued from North Entrance of the Padre Island National Seashore northward to San Luis Pass, including Corpus Christi Bay and Matagorda Bay. A Storm Surge Watch has been issued along the Texas coast east of High Island to Sabine Pass.

RDU is sticking out like a hot thumb again today with 102 at 4PM. This tweet from Brad Panovich says there’s a warm bias though much more during daytime than night: https://x.com/wxbrad/status/1809595420802261228?ref_src=twsrc^google|twcamp^serp|twgr^tweet The problem appears to not be with the sensor for that would mean just as much too hot at night, too, along with when it is cloudy, windy, etc. Rather, it appears per Brad to be due to the surroundings: “This is not an ideal siting situation for KRDU. Maybe I'm wrong, but that's way too much gravel and concrete and a building too close to the ASOS. Compare KRDU versus KCLT ASOS, which is surrounded by vegetation and no buildings” From here: https://x.com/wxbrad/status/1809626846633320508?ref_src=twsrc^tfw|twcamp^tweetembed|twterm^1809626846633320508|twgr^|twcon^s1_&ref_url= @eyewall

I’m closer to Ed on this. How Beryl handled shear a few days ago shouldn’t be all that relevant to how well she is handling shear now due to a much different storm structure vs then….imho.

Especially because the current structure is nowhere close to its structure of a few days ago when it rapidly deepened. For all practical purposes, it is like a different storm. Plus the atmosphere is far different though SSTs are similarly very warm.

Chuck, What's the deal with the lingering warmth in the top 75-100m right above the strong Nina in 100-250m corridor? I can't ever recall seeing something similar. Doesn't that cold water need to reach the sfc for it to impart a Nina-like reaction? It almost looks like a battle of the very warm oceans vs the forming Nina.

Also, RONI of 19-20 peaked at a mere +0.24 vs +0.55 ONI. So, not all that close to weak Nino on that basis.

Most recent progs I've seen are favoring something in-between E and W based with 3 and 3.4 about the same and warmer than 1+2 and 4. ....so neither.

The bolded is worth noting as another big difference from Harvey, which was blocked by highs both to the N and to the W. This resulted in incredibly slow movement once onshore, an avg of a mere ~2 mph over a 48 hour period resulting in historically high rainfall!

From Eric Webb at 1:42 PM EDT in response to Ryan Maue showing a sat. image of Harvey 48 hours prior to landfall: While I do agree that #Beryl may rapidly intensify into landfall in Texas later tomorrow, we need to pump the brakes on the “this could be Harvey all over again” paradigm. There are some truly gigantic differences between this and Harvey, in that during Harvey you started from basically nothing, whereas here w/ #Beryl you have a broad center and wind maxima that needs time to consolidate before really getting going again. Also, not to mention #Beryl’s environment isn’t exactly pristine, with a lot of mid-level dry air lurking to the south and moderate-strong southerly wind shear helping to force this dry air into the core. While there are a few exceptions, it’s **much, much** easier for a TC to intensify more quickly when you start with next to nothing like Harvey and just wrap up a tight initial inner core. Contrast that with #Beryl where you’re try to tighten up something that’s initially broad, with a lot more inertial stability to overcome. Historically speaking, most tightly wound cat 4-5s in the Atlantic that unwind then try to reintensify later on usually do so at a much slower pace, even in a great environments. This is likely because the broad pressure field left by the older, relic inner core pumps the breaks truly rapid intensification when it comes to surface winds. In these kinds of storms, you tend to get a lot more deepening, pressure falls, & a larger wind field at the expense of the peak winds having a harder time keeping up. I wouldn’t be surprised if that happens here w/ #Beryl https://x.com/webberweather/status/1809643994177237427?ref_src=twsrc^tfw|twcamp^tweetembed|twterm^1809643994177237427|twgr^|twcon^s1_&ref_url=

Dr. Levi Cowan’s latest: https://m.youtube.com/watch?v=4FpPjzTEt_w&embeds

Yes, it is ~-0.1. La Nada ONI. But RONI would likely be ~-0.6.

Not as strong on this run. 982 vs ~970.

Chuck, Is that due to the strong -PDO that has dominated since the 2nd half of 1998? https://www.ncei.noaa.gov/pub/data/cmb/ersst/v5/index/ersst.v5.pdo.dat

- The July Euro is forecasting ONI of ~-0.1C in ASO, which is a bit warmer than the June run. - The Euro runs over the last 15++ years have averaged too warm. My educated guess is that July has averaged 0.2 too warm for ASO. - Thus the implied bias corrected (bc) July Euro ASO ONI prog is for -0.3. - The latest ONI-RONI is +0.61 and has only slowly been falling from earlier record peak of +0.66. So, it’s realistic to assume an ASO ONI-RONI still up at ~+0.5. This means the bc July Euro prog for ASO RONI is ~-0.8. - Regarding implications for H season, I posted in late May that on avg the worst seasons for US H landfalls, especially NE Gulf to Carolinas, have been when ASO RONI was weak La Niña as opposed to either mod/strong Niña or cold neutral. This is also the case for the area from the Bahamas to Lesser Antilles. This was backed by maps that I saw elsewhere. - Thus, the bc July Euro prog for ASO RONI of ~-0.8 would be ~the worst ASO RONI from the perspective of one not wanting a bad season. That doesn’t mean it will be bad though as not all with a weak Niña have been. These are just averages. In May when I first studied this, it was looking like ASO RONI would be below -1.0, which would have had not as bad implications for the SE US to E Caribbean.

Indeed, Isidore had only 48 hours over water vs Beryl’s projected ~72 hours. Oh well, it wasn’t a big hope to begin with, especially due to Beryl’s much smaller size.

Do you think they can be "saved" by an Isidore-like very slow restrengthening as per my post above? I distinctly recall models/forecasters were almost unanimous in expecting a reintensifcation of Isidore back into a MH after moving off of the Yucatan due to the great organization, but the convection was very slow to reform.

The small hope I have is that Beryl struggles to re-intensify off of the Yucatan like the struggle of Isidore of 2002. Any thoughts? I remember this well. It was very large , which probably was a negating factor. Beryl is much smaller. Thus, my hope for a slow re-intensification like for Isidore is limited: "The inner core of convection collapsed while over southeast Mexico, and upon moving northward and reaching the Gulf of Mexico again, it was a large but weak tropical storm. Conditions favored significant strengthening, but Isidore did not redevelop central convection until reaching the northern Gulf of Mexico. The strengthening system hit Grand Isle, Louisiana on September 26 with maximum sustained winds of 65 mph (105 km/h)" https://en.wikipedia.org/wiki/Hurricane_Isidore To see how large Isidore was over the Yucatan, look at figure 4.a in here: https://www.nhc.noaa.gov/data/tcr/AL102002_Isidore.pdf

- So, verbatim, the July Euro is forecasting ONI of ~-0.1C in OND and NDJ. That compares to -0.3 in June and -0.5 in May. - The June runs over the last 15++ years have averaged a whopping 0.5 too warm for OND ONI. I haven’t analyzed July yet. But logically it should have a slightly smaller bias. Something like +0.3 to +0.4. - Thus implied bias corrected (bc) July Euro ONI prog is for -0.4 to -0.5 in OND/NDJ. - The latest ONI-RONI is +0.61 and has only slowly been falling from earlier record peak of +0.66. So, it’s realistic to assume an OND/NDJ ONI-RONI still up at ~+0.50. - Thus, the implied bc July Euro RONI prog is for -0.9 to -1.0 in OND/NDJ. The Euro and other progs look closer to a “basin-wide” than either E based or Modoki imo. - That -0.9 to -1.0 would be a much weaker La Niña than what many of us were earlier expecting as drop in Nino anoms was stalled for >month. However per @snowman19, Chris, Ray, and others, that might not make much of difference as far as winter is concerned due to the overwhelming W PAC warmth. - Regarding implications for H season, I posted in late May that on avg the worst seasons for US H landfalls, especially NE Gulf to Carolinas, have been when ASO RONI was weak La Niña as opposed to either mod/strong Niña or cold neutral. This is also the case for the area from the Bahamas to Lesser Antilles. This was backed by detailed maps I saw elsewhere. - The bc July Euro suggests an ASO RONI of ~-0.8, which would be ~the worst ASO RONI if one doesn’t want a bad season. That doesn’t mean it will be bad though as not all with a weak Niña have been. These are just averages. - Perhaps the long awaited resumed cooling is commencing. CDAS and CRW anomalies have dropped 0.1 to 0.2 in recent days. Also, the SOI has finally increased substantially the last 11 days (as expected per models). New easterly wind bursts have been mentioned by @snowman19and others. So, we’ll see.

1PM CDT: Beryl as expected downgraded to a TS/986 mb: NHC 1:00 PM CDT Fri Jul 5Location: 20.8°N 88.8°WMoving: WNW at 15 mphMin pressure: 986 mbMax sustained: 70 mph

The 12Z Euro is significantly NE of the 6Z’s CC landfall with it going ashore about dead-on mid TX coast. Also, it is much stronger at 971 mb vs 989 mb at 6Z! Those old ICON and JMA runs into Galveston are looking more realistic. There were a good number of runs of these two models in that vicinity. Example: ICON 12Z 6/30 run: (the 12Z 6/30 JMA was actually similar!) 12Z 6/30 JMA:

I can see it easily being significantly colder than last winter’s very mild winter in the NE, especially NNE. That shouldn’t be difficult to do. But these maps, everything else I’ve seen, and most indicators suggest the SE US will be much warmer than last winter’s only slightly AN as well as much drier.

Chris, after looking at this Euro map more closely, I see that >95% of the N Hem has H5 forecasted for NDJ to be >1 DM above the 1993-2016 based normal with 0% >1 DM BN. I usually think of 1 DM as the equivalent of ~1 F. So, this is suggesting 95% of the NH is forecasted to be 1+ F AN in NDJ. I guess that’s realistic considering how rapidly the globe has been warming since 1993 thus suggesting true up to date normals are probably a whopping ~2F warmer than 1993-2016. Does that seem right? Do you think it has warmed that rapidly?

12Z GEFS: increase in strong members to the NE (I see at least 5 members there between strong cat 1 and cat 2):

12Z UKMET landfall is all of the way up to Corpus Christi. The 0Z run was in NE MX. But this isn’t at all surprising considering clearcut N trends. 12Z CMC at MX/TX border, which is ~100 miles N of 0Z run. It is still the furthest S landfall by far compared to the ICON (Galveston), GFS (CC), and UKMET (CC).