####018005399#### FXUS64 KCRP 070808 AFDCRP Area Forecast Discussion National Weather Service Corpus Christi TX 308 AM CDT Tue May 7 2024 ...New SHORT TERM, LONG TERM, MARINE... .SHORT TERM... (Today through Wednesday) Issued at 255 AM CDT Tue May 7 2024 Key Messages: ▶ There's a moderate to major risk for heat related illness Tuesday and Wednesday ▶ There's a Moderate Risk for Rip currents through Wednesday morning The region will be under a zonal flow aloft with a mid-level low pressure system over the northern Plains and a mid-level high over western Mexico. There's a few disturbances that will move across the region and will keep silent PoP's in the forecast but expecting the CAP to be a major limiting factor. The big story here will be the heat. WAA in the lower to mid levels will combine with humid conditions near the surface resulting in a Moderate to a Major risk of heat related impacts across the region Tuesday and Wednesday, According to the NWS Heat Risk tool. Currently, there's a low to medium chance (30-40%) for Heat Indices of at least 110 degrees across the southern Coastal Plains and southern Coastal Bend for a few hours on Wednesday afternoon. A Heat Advisory may be needed but will hold off issuing for now. Regardless, Don't get caught off-guard by the first heat of summer as temperatures will ramp-up quickly. Take proper precautions for heat safety, have a plan to stay cool and hydrated, have multiple ways to receive weather alerts and warnings. Have opted to let the Coastal Flood Advisory and the High Rip Current Risk to expire this morning as swell heights/periods have decreased to around 3 ft and 7 seconds respectively. Will keep a moderate risk for rip currents through the period. && .LONG TERM... (Wednesday night through next Monday) Issued at 255 AM CDT Tue May 7 2024 Key Messages: - There is a moderate to major HeatRisk Thursday. - A front Thursday night will usher in drier air and return temperatures to near normal for this time of year. - Moisture returns to the region this weekend bringing increasing rain chances into early next week. Another day of intense heat is expected Thursday with heat index values ranging from 105 to 113 degrees across the region, highest across the inland Coastal Bend. Heat advisories will likely be needed for some locations. Relief to the heat is in store Friday into the weekend as a cold front moves through Thursday night. Confidence in any precipitation with the front remains very low, but if any storms do manage to form, the best chance would be near or north of the Victoria Crossroads. The front will stall out around the area over the weekend with a low (15-30%) chance of showers and thunderstorms. Deeper moisture looks to stream back in by Sunday. This increase in moisture combined with the subtropical jet setting up over the area and embedded shortwave troughs could lead to increased rain chances late this weekend into early next week. Current long range ensemble models have about a 30 percent chance of at least a quarter inch of rain across much of the Coastal Plains and around a 15 percent chance of at least an inch of rain. This is still a ways out and plenty of uncertainty remains, but it certainly warrants keeping an eye on over the next few days. && .AVIATION... (06Z TAFS) Issued at 1020 PM CDT Mon May 6 2024 The cloud cover is moving back into the region with the clouds at the coast, with IFR/MVFR CIGs near the coast (NGP) and beginning to move in (few009 at CRP 04Z). The clouds will continue to move inland and will get to LRD and COT somewhere around 08z-10z. Will expect IFR CIGs through the morning before the clearing out again around 15 or 16z. CIGs will remain VFR with occasional MVFR through 00z, and then the clouds will move back into the forecast area, and spread back to the west. && .MARINE... Issued at 255 AM CDT Tue May 7 2024 A weak to moderate onshore flow increases to moderate flow early Wednesday. There is a very low chance (less than 15%) for showers or thunderstorms today. Moderate onshore flow will continue through Wednesday night. Winds will diminish Thursday ahead of an approaching cold front. Winds will shift to the northeast Friday and Saturday, then to the east on Sunday. There is a 15-30% chance of showers and thunderstorms through the weekend. && .PRELIMINARY POINT TEMPS/POPS... Corpus Christi 91 77 96 76 / 0 0 0 0 Victoria 91 74 92 74 / 0 0 0 0 Laredo 101 77 107 76 / 0 0 0 0 Alice 96 74 102 73 / 0 0 0 0 Rockport 86 77 87 77 / 10 0 0 0 Cotulla 98 77 104 75 / 0 0 0 0 Kingsville 93 75 100 74 / 0 0 0 0 Navy Corpus 87 78 89 78 / 0 0 0 0 && .CRP WATCHES/WARNINGS/ADVISORIES... TX...High Rip Current Risk until 7 AM CDT this morning for TXZ345-442- 443-447. Coastal Flood Advisory until 10 AM CDT this morning for TXZ345- 442-443-447. GM...None. && $$ SHORT TERM...BF/80 LONG TERM....CLM/93 AVIATION...JSL ####018006028#### FXUS64 KSHV 070808 AFDSHV Area Forecast Discussion National Weather Service Shreveport LA 308 AM CDT Tue May 7 2024 ...New SHORT TERM, LONG TERM... .SHORT TERM... (Tuesday through Wednesday) Issued at 249 AM CDT Tue May 7 2024 Early morning NT Microphysics imagery shows low clouds streaming north across the FA, as upper-level sheared cirrus from deep convection across OK/AR drifts west to east, just north of the I-30 corridor. For the most part, Tuesday will remain dry and quiet, with the main story through the afternoon being the warmer temperatures as highs climb into the upper 80's to near 90 deg F. Given the extent of the diurnally driven sfc heating this afternoon, hi-res guidance advertises an aggressive display of surface-based instability parameters across the Four State Region with SBCAPE values as high as 3000-3500 J/kg or greater, with 0-6 km bulk shear values between 40-50 kts, and 700-500 lapse rates between 7-8 C/km. The catch here is that while this may be available, guidance looks to leave it mostly untapped as forcing remains well displaced from the local coverage zone, primarily located in a region of better synoptic forcing and ascent well to the north and east of the local area. Morning guidance continues to suggest that a residual sfc boundary may exist close to the I-30 corridor this afternoon from overnight convection across Oklahoma. This boundary should wash out and lose it's potency due to afternoon mixing. It is worth mentioning that some CAMs do suggest a secondary instability axis to drift north into the better sfc parameters, supporting some limited convective initiation by the evening, but by this point it may be too late for any deeply rooted convection to evolve. Main concerns if any thunderstorms are to develop along the instability axis would be the threat for gusty winds and hail. This would be located mainly in the Marginal risk zone (level 1 of 5), highlighted in the Storm Prediction Center Day 1 outlook. Wednesday Severe Threat: By Wednesday morning, better forcing starts to dig into the Southern Plains, with a sfc cold front advancing southward, progged to enter into the Four State Region by mid to late Wednesday afternoon. Another warm afternoon across the FA will promote further sfc instability as high temperatures easily climb to 90 deg F and possibly a degree or two higher. As the boundary clashes with the local airmass, deeply rooted convective initiation will look to develop across a region of high SBCAPE profiles approaching, and possibly even exceeding, 3500 J/kg, 0-6 km bulk shear between 40-50 kts, and steep lapse rates nearing 8.0 C/km. Though some low level directional shear will be present, supporting the chance for a tornado or two, the main concern from the advertised CAMs and HREF solution will be the threat for large hail within the Enhanced risk (level 3 of 5). Based on latest guidance, convection should diminish ahead of sunrise Thursday. RK && .LONG TERM... (Wednesday Night through Tuesday) Issued at 249 AM CDT Tue May 7 2024 By Thursday morning, the forward speed of the advancing sfc boundary will dictate the coverage of the day 3 severe threat locally. General thinking for now is that the boundary will be located somewhere between I-30 and I-20, and is progged to slide south through the afternoon. Afternoon maxT's south of the boundary will climb into the upper 80's and low 90's, with instability parameters strongest in this region. Frontal based forcing will support convective initiation along and ahead of the boundary by the afternoon, and continue into the evening in the form of a possible MCS. Primary concerns with the developing convection is the threat for damaging wind, and large hail. The chance for an embedded tornado should not ruled out. The front will sag south of the FA by Friday AM, with high pressure influencing the region for much of Friday and into weekend. Guidance overnight now keeps much of the area rain free till about early to mid next week. Post frontal passage airmass will help return temps to near normal through the remainder of the forecast period. RK && .AVIATION... (06Z TAFS) Issued at 1207 AM CDT Tue May 7 2024 MVFR ceilings rapidly returning northward from SE TX and SW LA into our airspace at this late hour this evening and thus, expect widespread MVFR ceilings to dominate much of our region through the predawn hours. Cannot rule out a narrow window of IFR ceilings at the LFK terminal a couple hours either side of sunrise but given the low level pressure gradient in place, feel like MVFR ceilings are the better bet vs IFR ceilings across our airspace through mid to late morning when ceilings return to low VFR variety. Latest HRRR wants to develop a narrow line of showers/Isolated TSRA from near LFK to SHV to ELD terminals and keeps this activity in the same general locations through the middle afternoon. Cannot find any support for this activity in other model output so will leave it out of this 06z TAF package and will reassess with the 12z package. Look for SSE to SSW winds today to be near 8-12kts sustained with gusts upwards of 20kts, especially across our NE TX terminal locations. 13 && .PRELIMINARY POINT TEMPS/POPS... SHV 89 74 90 72 / 10 10 20 40 MLU 88 73 91 71 / 10 0 10 40 DEQ 86 66 85 63 / 20 20 30 50 TXK 89 72 90 68 / 10 20 30 60 ELD 88 70 90 67 / 20 20 20 60 TYR 88 71 89 71 / 10 10 30 30 GGG 88 72 90 70 / 10 10 30 30 LFK 89 72 91 73 / 10 0 10 10 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...None. LA...None. OK...None. TX...None. && $$ SHORT TERM...53 LONG TERM....53 AVIATION...13 ####018009109#### FXUS61 KBUF 070809 AFDBUF Area Forecast Discussion National Weather Service Buffalo NY 409 AM EDT Tue May 7 2024 .SYNOPSIS... High pressure will bring abundant sunshine today, with temperatures quickly warming after a cool start. A warm front will then move across the area tonight, with an area of showers and a few thunderstorms crossing the area from southwest to northeast. The showers will exit the eastern Lake Ontario region Wednesday morning. Dry weather will then prevail most of the time for the rest of Wednesday, although a few more showers and thunderstorms are possible later in the afternoon and evening, especially east of Lake Ontario. Unsettled weather will then last Thursday through the weekend with a series of low pressure systems crossing the region. && .NEAR TERM /THROUGH WEDNESDAY/... High pressure will move from Ontario and Quebec east across New England today. Full sunshine will prevail most of the day, with a modest increase in high clouds later this afternoon. Temperatures are in the 40s across the bulk of the area early this morning, and even a few upper 30s east of Lake Ontario and in the colder sheltered valleys of the Southern Tier. Temperatures will quickly warm today after the cool start, with highs in the low to mid 70s in most areas. A light northeast flow will keep the south shore of Lake Ontario much cooler. Tonight through early Wednesday morning a mid level trough will move northeast across the Great Lakes, with an associated warm front moving northeast across our area overnight. A 40+ knot southwesterly low level jet in the upstream warm sector will impinge on the warm front and enhance moisture transport and isentropic upglide. The quality of forcing and moisture continue to support the idea of an organized area of showers moving from southwest to northeast across the area overnight. Expect an arrival time of late evening in far Western NY, around or shortly after midnight for the Genesee Valley and western Finger Lakes, and the pre-dawn hours east of Lake Ontario. Forecast soundings show enough elevated instability to support a few thunderstorms as well. Wednesday, the warm front will still be over the eastern Lake Ontario region early in the morning with showers and a few isolated thunderstorms. Rain will have already ended across Western NY as the better forcing and moisture move east. The warm frontal showers will largely end by mid to late morning east of Lake Ontario. A strong mid level shortwave will then move across southern Ontario in the afternoon, crossing northern NY during the late afternoon and early evening. Diurnal instability will increase by this time, aided by steep mid level lapse rates within a remnant EML plume crossing the Ohio Valley into PA and portions of NY. The increase in large scale forcing and instability will support another round of scattered showers and thunderstorms east of Lake Ontario later Wednesday afternoon and evening. A few of these storms may contain gusty winds and small hail, with a Marginal Risk of an isolated severe storm or two per the SPC Day 2 outlook. Farther west, Wednesday will stay mostly dry from Western NY into the Genesee Valley. A relatively dry and capped warm sector will be difficult to overcome for any deep moist convection that attempts to develop. In addition, a gusty WSW breeze will develop off Lake Erie, with a stable lake shadow expanding inland during the afternoon. The best chance of a few isolated showers will be along the northern edge of the stable flow off Lake Erie, from the Niagara Peninsula east across the Niagara Frontier to areas along the south shore of Lake Ontario. Finally, an increasingly moist airmass crossing the cold lake waters will likely produce marine layer fog late tonight through Wednesday morning. Some of the Lake Erie fog will likely move onshore into downtown Buffalo for a few hours Wednesday morning. Some of the Lake Ontario fog may move onshore into Jefferson County as well. && .SHORT TERM /WEDNESDAY NIGHT THROUGH THURSDAY NIGHT/... A weak area of low pressure will be east of the forecast area Wednesday night. Isolated showers will persist east of Lake Ontario Wednesday evening before tapering off after midnight. Dry conditions are expected across the remained of the forecast area. Mostly cloudy conditions with low temperatures in the upper 40s to low 50s. A shortwave trough across the Mid-Western states will approach the region Thursday. A westerly flow aloft will become southerly by late Thursday and moisture and warm air advection will increase the chance for showers across the region. An associated area of low pressure will move south of the forecast area through Thursday night while the shortwave trough deepens across the Northeast. While there is uncertainty in the track and strength of this system, periods of showers are likely ahead of this system Thursday into Thursday night. There is a slight chance of thunderstorms during peak heating Thursday afternoon, however confidence is low. Rainfall amounts will average 0.25-0.50 inches across the region Thursday through Thursday night. Temperatures will average slightly above normal Wednesday night and Thursday night, however a northeast wind across the region Thursday will keep high temperatures slightly below normal. && .LONG TERM /FRIDAY THROUGH MONDAY/... An upper level trough will become nestled across the Great Lakes region and Northeast through the weekend. This will bring unsettled and cooler weather across the eastern Great Lakes region. Initially, an area of low pressure should be departing to the east of the region Friday. The 00z GFS/GEFS is an outlier at this point and keeps the area of low pressure over to the region. Daytime heating and cooler temperatures aloft will likely lead to showers developing across the region Friday. Drier weather is expected Friday night into Saturday as a ridge briefly moves into the region, however any clearing and daytime heating may result in scattered showers Saturday. The upper level trough will move overhead while the surface low pressure approaches the region Sunday into Sunday night. There are low to medium chances for showers to end the weekend. The trough will move east of the region the start of the work week with chances for showers lingering into Monday. While confidence is low on the coverage and timing of showers Friday through Monday, confidence is higher that it will be a period of cooler weather across the eastern Great Lakes region. Temperatures will average below normal with temperatures reaching near normal by Monday. && .AVIATION /08Z TUESDAY THROUGH SATURDAY/... High pressure will drift east across Ontario and Quebec today, reaching New England by late afternoon. VFR will prevail areawide with clear skies and light winds. Tonight, a warm front will move quickly northeast across the eastern Great Lakes. Expect an area of showers and possibly some embedded thunder to cross the area from southwest to northeast overnight. Expect the rain to reach Western NY around midnight, then move to the eastern Lake Ontario region by daybreak. The rain will be moving into a dry airmass, so expect mainly VFR CIGS/VSBY initially. The low levels will saturate near the back edge of the rain, with areas of MVFR/IFR CIGS expanding late tonight. Outlook... Wednesday...Areas of MVFR/IFR CIGS in the morning, improving to mainly VFR in the afternoon. A chance of showers and thunderstorms, mainly east of Lake Ontario. Thursday...VFR/MVFR. Showers likely with a chance of thunderstorms. Friday...MVFR. Showers likely. Saturday...Mainly VFR. A slight chance of showers. && .MARINE... High pressure will drift east across New England and weaken today. Winds will be light for most of the area. The one exception will be the west end of Lake Ontario, where ENE winds will increase this afternoon and evening, producing choppy conditions on Lake Ontario west of Rochester, but winds and waves are generally expected to remain below Small Craft Advisory criteria. WSW winds will increase Wednesday, especially on Lake Erie. This will produce very choppy conditions Wednesday through Wednesday evening, possibly near Small Craft Advisory criteria. An increasingly moist airmass crossing the cold lake waters will likely produce marine layer fog late tonight through Wednesday morning on Lake Erie and Lake Ontario with visibility restrictions. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...None. MARINE...None. && $$ SYNOPSIS...Hitchcock NEAR TERM...Hitchcock SHORT TERM...HSK LONG TERM...HSK AVIATION...Hitchcock MARINE...Hitchcock