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| #1222842 (Received by flhurricane at: 1:06 AM 14.Mar.2025) AFDHGX Area Forecast Discussion National Weather Service Houston/Galveston TX 1147 PM CDT Thu Mar 13 2025 ...New AVIATION... .SHORT TERM... (This evening through Friday Night) Issued at 357 PM CDT Thu Mar 13 2025 It`s a little toasty out there huh?! 3pm temperature observations reflect widespread readings in the upper 80s and there`s still another hour to go till peak heating...you do the math. This is due to PW values around the 10th percentile coinciding with 850mb temperatures around or above the 90th percentile...so conditions are very favorable for well above normal temperatures. Houston/Bush Airport has already broken their record high temperature for today and Houston/Hobby Airport and College Station are fairly close to theirs (see Climate section below for today`s records). Expecting widespread high temperatures in the upper 80s with some locations reaching the low 90s this afternoon. And while that`s going on, sea fog has begun to move into Galveston. Based on one of the seawall webcams, we went from being able to see the Pleasure Pier one minute and it was completely gone the next. For those wanting to catch a glimpse of the Total Lunar Eclipse on early Friday morning, listen up! Onshore flow returns tonight leading to increasing low-level moisture and cloud cover. Skies will be becoming mostly cloudy for most of the area around the beginning of the total eclipse (~1:26 AM CDT Friday morning). Locations along the coast will also be battling against the increasing potential for patchy fog, so definitely pack your patience if you`re planning on heading outside to catch a glimpse of the moon as it turns a reddish hue. Expecting low temperatures in the low to mid 60s tonight, but it`s important to note that temperatures will be on the rise in the early morning hours as WAA and moisture advection increase in response to surface low developing in the Central Plains. This is in response to an increasingly negative tilted upper-level low drifting towards the TX/OK panhandles on a northeastward track. It`s also worth noting that isentropic lift along the coast tonight could bring some scattered light rain showers into early Friday morning. Expecting another round of well above normal temperatures on Friday with high temperatures in the mid to upper 80s. Some low 90s can`t be ruled out around Matagorda Bay, but increased moisture should keep temperatures a couple of degrees lower than today (Thursday). A dry line will push into the Brazos Valley on Friday afternoon with a slight chance of showers/storms along and pushing ahead of the boundary. Best rain chances will be well east of the I-45 corridor. There is a marginal risk (level 1 of 5) for strong to severe storms for eastern Trinity and Polk Counties mainly for the potential for hail if a storm is able to break the cap. The cold front associated with this system only partially pushes through the Brazos Valley on Friday night, so expecting quite the contrast in low temperatures. North of the frontal boundary, expecting low temperatures in the low to mid 50s. South of the frontal boundary, expecting low temperatures in the 60s along with patchy fog. Batiste && .LONG TERM... (Saturday through next Wednesday) Issued at 357 PM CDT Thu Mar 13 2025 Key Messages: -Fire Weather Watch Saturday -Marginal Risk for Severe Weather on Saturday for line from Freeport to Livingston and east Cold front is still on track to pass through the area Friday night into early Saturday. The FROPA should move offshore by mid-morning Saturday, leaving behind a very dry and breezy airmass. Some storms associated with the frontal boundary could become strong to severe, with damaging winds as the main threat. Winds will become westerly and as the pressure gradient tightens, winds will increase to 10-15 mph with gusts to above 30 mph through the afternoon hours. In addition to the winds, dew points are expected to drop into the 30s and RH values are expected to drop into the teens to low 20% range Saturday afternoon. As a result, critical fire weather conditions are expected to continue into Saturday. A Fire Weather Watch is in effect for Saturday, and will likely be upgraded to a Red Flag Warning with a later forecast package. A secondary cold front will bring a reinforcement of drier and cooler air on Sunday as winds become northerly. Temperatures will top out in the low to mid 70s along and N of I-10, while south of I-10 will see highs in the mid to upper 70s. Lows on Sunday night will drop into the mid 40s to low 50s. Warm and humid conditions will return early next week as highs rebound in to the low 80s by Tuesday. The return of warm and humid conditions will be brief as another FROPA is expected for Wednesday. Dry and breezy conditions will follow behind the front. Will need to monitor for the potential for another round of elevated Fire Weather conditions Wednesday afternoon into Thursday. Dry cool air will return behind the front, keeping lows in the upper 40s to low 50s Wednesday night and highs in the upper 60s to low 70s for Thursday. Adams && .AVIATION... (06Z TAF Issuance) Issued at 1030 PM CDT Thu Mar 13 2025 IFR to MVFR condtions are expected for the majority of the area within the next few hours due to the development of CIGs between 500-1500ft. However, GLS will remain in IFR to LIFR through the night due to coastal fog with VV of 200ft and visibility down to 1/2 miles at times. Fog will be possible at further inland sites up through I-10 with visibility down to 3-6 miles with elevated winds of 5-9kt will limit develoment futher north. A strong low level jet is expected to develop overnight, so while winds at the surface will generally be below 10kt, winds increase to 35-40kt at around 2000ft. Some of these higher winds will mix down to the surface by the mid-morning with gusts to 20-25kts expected to continue through sunset. MVFR to IFR conditions due low clouds and patchy fog return between 3-6z for I-10 southwards, and then expand northwards by 9z. Fowler && .MARINE... Issued at 357 PM CDT Thu Mar 13 2025 Light southwest winds and seas of 2 to 4 feet are expected today. Patchy fog is occurring in the Galveston Bay area this afternoon ahead of the front. Expect fog potential to continue for the bays and nearshore waters up to the point of the frontal passage. Winds will become south to southwest on Friday and increase to moderate as the local pressure gradient tightens ahead of a dry cold front. The front is expected to move into the coastal Gulf waters sometime Saturday morning. Winds briefly become westerly on Saturday and then northwesterly on Sunday in the wake of another reinforcing dry cold front. Sunday evening into Monday, winds will go from northeast to southeast as high pressure moves over Southeast TX and departs to the east. Moderate onshore flow will return Tuesday into Wednesday ahead of another cold front, progged to push off the coast sometime Wednesday afternoon. Moderate to occasionally strong offshore winds can be expected in the wake of the front. Adams && .FIRE WEATHER... Issued at 357 PM CDT Thu Mar 13 2025 UPDATE: A Red Flag Warning has been issued for Friday for portions of the Brazos Valley and the Piney Woods. A Fire Weather Watch has been issued for Saturday for most of Southeast Texas. Both are due to elevated southwesterly/westerly winds alongside low relative humidity values leading to critical fire weather conditions. -Batiste Back and forth, back and forth - we get a dry day, then a windy day. Rinse and repeat. That makes today a *checks notes* dry day! The weak front/dryline/whatchamacallit is quite weak and diffuse. It really is much more like a dryline, which means on the backside of the boundary we`ve got hot and dry air, which means very low RH - that is, 25-40 percent lower than yesterday`s min RH values! Things really only get boosted by the light west/southwesterly flow, which tends to be a warmer, drier flow that is downsloping off higher terrain. Fortunately, these winds are much weaker than yesterday. This doesn`t eliminate fire weather concerns as it is very dry, but it does at least keep them from being critically dangerous. Still, with min RHs in the teens west of the Houston metro in an area that tends towards finer fuels, locally elevated fire weather issues can emerge. The key fuel type to watch for would be dense beds of fine, grassy fuels. These will react most strongly to the low RH, and a high density will make spread possible with less wind. Tomorrow, we put the thing (fire weather parameters) down flip it, and reverse it. Winds will be stronger again - in the area of 10 mph sustained with gusts to around 20 mph. Still not critically high, but enough to take note - especially if we see frequent gustiness. However, these stronger winds will also be more southerly. This gives us a more direct Gulf connection and more humidity filtering inland from the water. It doesn`t look to be a huge increase in moisture, but enough that we flip the primary fire weather concern from very low RH to the gustier winds. This is a nice development, as I was a bit concerned about Friday being a deceptively dangerous day where neither the winds nor RH were as extreme as other days, but bad enough and finally overlapping to cause serious issues. It seems winds back enough to hold the really dry air at bay. However, folks way inland will be the last to see RH respond to the onshore flow, and so our northwest corner isn`t out of the woods yet. Specifically, I`m keeping an eye on Burleson, Brazos, and Washington counties. For broader concerns, I`m now keeping my eye on Saturday. Winds look to be west/southwesterly to due westerly behind the next weak front. This puts us back in a hotter, drier wind regime. Again, I`d expect RH even right on the water to fall to around/below 40 percent, and wide swaths of inland areas dipping into the lower 20s and teens. The big question is...how strong will those winds be? If my deterministic forecast is perfect, we`d be looking at sustained winds around 15 mph and gusts into the 20s west of the Houston metro - more specifically, west of the Brazos. And with little rain and several dry days, forecast ERC values in that area are now pushing above the 50th percentile, meaning fuels are becoming drier than typical. Taking a more probabilistic view, the LREF probability of getting 20/20 conditions (less than 20 percent RH and wind speeds greater than 20 mph) is 10-20 percent on Saturday west of the Houston metro. If we step the wind threshold down to 15 mph, those probabilities increase to 30-50 percent. This isn`t quite enough confidence for me to decide on a fire weather watch for Saturday just yet, but we definitely need to watch our western edge for sure. Luchs && .CLIMATE... Issued at 357 PM CDT Wed Mar 12 2025 Dry air and southwesterly winds are expected to bring the hottest temperatures of the year (so far) today, March 13th. Another round of well above normal temperatures is expected for Friday as well. With high temperatures anticipated to be at least near record territory for the next couple of days, here are the daily record high temperatures for March 13th & 14th: March 13th: -College Station: 90F (1918) -Houston (Bush Airport): 88F (1942) -Houston (Hobby Airport): 89F (1942) -Palacios: 81F (2020) -Galveston: 81F (2006) March 14th: -College Station: 90F (1936) -Houston (Bush Airport): 88F (2008) -Houston (Hobby Airport): 88F (2016) -Palacios: 80F (1982) -Galveston: 80F (1922) Batiste && .PRELIMINARY POINT TEMPS/POPS... College Station (CLL) 63 87 54 77 / 0 0 20 0 Houston (IAH) 65 86 63 79 / 20 10 10 10 Galveston (GLS) 66 77 64 75 / 10 20 0 10 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...Red Flag Warning from noon to 9 PM CDT Friday for TXZ163-176- 195>198. Fire Weather Watch from Saturday afternoon through Saturday evening for TXZ176>178-195>199-210>213-226-227-235>238-313- 335>337. Dense Fog Advisory until 10 AM CDT Friday for TXZ436>439. GM...Dense Fog Advisory until 10 AM CDT Friday for GMZ330-335-350-355. && $$ |
| #1222841 (Received by flhurricane at: 12:57 AM 14.Mar.2025) AFDLIX Area Forecast Discussion National Weather Service New Orleans LA 1155 PM CDT Thu Mar 13 2025 ...New AVIATION... .UPDATE... Issued at 916 PM CDT Thu Mar 13 2025 Performed an early update to the Coastal Waters Forecast to add a Marine Dense Fog Advisory for much of the inner open waters around Southwest Pass, Breton and Chandeleur Sounds and Lake Borgne. Web cameras at Pilottown and Burrwood had already shown fog developing as 70 degree air was flowing over 50 degree water temperatures. Have to assume that similar conditions exist at the mouth of the Atchafalaya. For now, have held off on a Fog Advisory over land, as we haven`t sen any reduced visibilities quite yet. Won`t rule out one being issued during the overnight hours. Low temperature forecast looks to be pretty reasonable at this time. ZFP update is mainly to eliminate the afternoon forecast period. && .SHORT TERM... (This evening through Friday night) Issued at 334 PM CDT Thu Mar 13 2025 Shortwave trough axis moving across the northern Gulf Coast is now east of the region and will be tracking into the open Atlantic tonight. Virtually no local sensible changes have yet to come from this system other than just isolated showers around the CWA. A swath of drier mid level air is following behind the shortwave and will bring a dip in PWs this evening but it will be shortlived. Strong southerly flow west of the CWA will surge Gulf moisture northward across the LA/TX border. An upper level trough currently moving through southern California will develop into a closed low as it swings across the Texas Panhandle late tonight and the Central Plains. Either a frontal boundary or dryline associated with this feature will race east through Texas Friday. THat moisture surge mentioned above will get pushed east into the CWA Friday afternoon. Model soundings around the CWA show some decent upper level cooling and leading to plenty of elevated instability. Afternoon highs in the 80s will play a part in whether any storms that do develop become surface based. Low level inversion/cap probably won`t erode south of I-12 but along and north of there stands a better chance for that to happen. It`s in this region of the local area that the potential for isolated storms with severe hail and/or winds is greatest. && .LONG TERM... (Saturday through Wednesday night) Issued at 334 PM CDT Thu Mar 13 2025 Bigger impacts coming this weekend. Confidence continues to increase for the potential of a severe weather outbreak across portions of the Gulf Coast states with a Moderate Risk now in the SPC severe outlook Day 3. It takes a fair amount of confidence to put that out to the public this far out. The system coming is a bit different than our more recent severe weather event. Current model solutions show a trough coming in from the west while the Central Plains upper low is curling up the upper Mississippi Valley. It never really turns negatively tilted because its so broad but not sure how much that matters as the 300mb jet coming around the base of it is sourced from a 150+kt jet and will still be plenty fast as it passes the apex of the trough. The shape of the trough also factors into the winds throughout the column. Vertical wind shear will be more than ample ranging from 30 to 60 knots based on height but the directional shear is where there`ll be more limitation. The south winds become more southwesterly as the trough approaches which then lowers helicity values. While not optimal for increasing tornado potential, not sure how much it`ll really matter as values of 150- 300 m2/s2 are sufficient. That`s especially true with so much instability developing as low level cap erodes and surface temps warm. Should note that do have some concern that stubborn marine layer will come into play, especially along/south of I-10 in LA and even MS. Some model soundings actually show the MS coast stuck under an inversion the entire event. Surface warming will be critical there for any storms to be surface based. That doesn`t seem to be as much of a problem north of I-10 in MS and north of I-12 in LA but will note that weak low level instability could hinder updraft strength of some to all storms. Pre-event light showers and associated cloud cover could be part of that surface temp limitation. In terms of timing, really not much change between model runs which is good for confidence in that portion of the forecast. So generally thinking window of greatest threat is mid morning through mid evening Saturday. && .AVIATION... (06Z TAFS) Issued at 1148 PM CDT Thu Mar 13 2025 Currently, KHUM near field minima in fog, with remaining terminals at VFR. Starting to see some MVFR ceilings between KBTR and KMSY, though. Do expect most or all terminals to deteriorate to IFR conditions in the next 4 hours or so, with some potential for LIFR or VLIFR conditions for a few hours around sunrise. Don`t have enough confidence to go with VLIFR as a prevailing at remaining terminals though. Expect improvement to MVFR by 14-15z, and probably VFR during the afternoon at several terminals, if not all. Lower clouds will return beyond sunset, likely MVFR ceilings. Isolated TSRA wouldn`t be a total surprise in the 00z-06z window, but better chances beyond 06z Saturday. Winds also likely to be an issue for east-west runway configurations beyond 15z Friday with gusts to 25 or 30 knots possible at most terminals. && .MARINE... Issued at 334 PM CDT Thu Mar 13 2025 A shortwave trough is now east of the CWA and will weaken as it moves into the western Atlantic. This will allow for the surface high to build back into the Gulf of America Friday. Therefore, expect a range onshore flow to persist but remain limited. Stronger winds and higher waves/seas will accompany a system moving through the country this weekend. A deep trough will dive into the deep south while a deepening low swings north through the upper Mississippi Valley Saturday. Expect strong onshore gradient winds as the associated cold front approaches. Small Craft conditions are a given...gale criteria is less certain. So went ahead and issued a Small Craft Advisory for Friday night through Saturday night timeframe. Although winds behind the front should be at/above 20kts, it probably won`t be long as very progressive pattern brings post frontal surface ridge to the northern Gulf coast very quickly. && .PRELIMINARY POINT TEMPS/POPS... MCB 60 81 66 78 / 0 20 60 90 BTR 64 84 70 81 / 0 20 50 90 ASD 62 81 69 81 / 0 10 50 90 MSY 64 81 70 81 / 0 10 30 90 GPT 62 76 65 75 / 0 10 40 90 PQL 61 79 66 78 / 0 10 40 80 && .LIX WATCHES/WARNINGS/ADVISORIES... LA...None. GM...Small Craft Advisory from 7 PM Friday to 7 AM CDT Sunday for GMZ530-532-534-536-538-550-552-555-557-570-572-575-577. Dense Fog Advisory until 10 AM CDT Friday for GMZ534-536-538-550- 552-555. MS...None. GM...Small Craft Advisory from 7 PM Friday to 7 AM CDT Sunday for GMZ532-534-536-538-550-552-555-557-570-572-575-577. Dense Fog Advisory until 10 AM CDT Friday for GMZ536-538-550-552- 555. && $$ |
