####018005405#### FXUS64 KBRO 161743 AAB AFDBRO Area Forecast Discussion...UPDATED National Weather Service Brownsville TX 1243 PM CDT Fri May 16 2025 ...New AVIATION... .SHORT TERM... (Today through Saturday) Issued at 316 AM CDT Fri May 16 2025 The main concern in the short term will be the oppressive daytime heat. The 500mb subtropical ridge will continue to bring dry and hot summer-like conditions over Deep South Texas through the period. Near record to record high temperatures will be possible today and Saturday. The combination of the unseasonable hot temperatures and higher humidity will support heat indices between 105 to 110 degrees across most of Deep South Texas this afternoon, which is just below Heat Advisory criteria. The temperatures and dewpoints appears slightly too high based on previous surface observations and current trends. Therefore, made minor adjustments to the hourly daytime temperatures. Decided to use a 50/50 CONSShort/NBM blend for dewpoints. An SPS has been issued for Starr and Hidalgo to Brooks and Kenedy counties due to brief Heat Index values 110 to 113 degrees this afternoon. A Heat Advisory may be needed Saturday across the same area, with slightly higher humidity values forecast. A majority of the CWA is under a Major Risk (level 3 of 4) of heat- related illness for today and Saturday. Isolated areas of Extreme (level 4 of 4) Heat Risk will be possible this afternoon and Saturday afternoon across portions of the ranchlands and Rio Grande Plains. An slightly enhance pressure gradient will lead to moderate to breezy south to southeast winds through the period. There is a Moderate Risk of rip currents at local beaches today through Saturday. && .LONG TERM... (Saturday night through Thursday) Issued at 316 AM CDT Fri May 16 2025 The subtropical ridge holds a dry and hot summer-like pattern across Deep South Texas into mid-week. Persistent low pressure across the Plains, with a surface ridge anchored across the eastern Gulf, will maintain an enhanced pressure gradient locally and increase humidity into Tuesday. A cold front drops south mid to late next week, potentially stalling across the ranchlands, with a surface ridge building across the Plains into South Texas. This will finally provide some relief from the heat, less wind, and more comfortable humidity values. POPs remain very low. Heat Advisories may be needed Monday and Tuesday. Heat Risk levels range from Moderate (level 2 of 4) to Extreme (level 4 of 4) Sunday and Monday, with Moderate to Major (level 3 of 4) on Tuesday. Record highest low temperatures will once again become threatened, especially Monday and Tuesday mornings. && .AVIATION... (18Z TAFS) Issued at 1233 PM CDT Fri May 16 2025 VFR at all sites to continue through Friday afternoon with gusty southerly winds. Inconsistent gusts around 26 kts will continue through the afternoon at HRL and BRO. Cloud coverage begins to build this evening, bringing MVFR conditions to all sites at or beyond sunset. All sites may experience temporary drops to IFR early Saturday morning, however, less confidence at MFE - hence no TEMPO. Winds calm a bit overnight, with gusts around 20 kts. && .MARINE... Issued at 316 AM CDT Fri May 16 2025 Today through Saturday...A slightly enhanced pressure gradient will produce weak to moderate southeast flow and moderate seas through the period. Small Craft Exercise Caution conditions are expected on the Laguna Madre and the Gulf waters today into Saturday due to elevated winds and/or seas. Saturday Night through Thursday...Moderate southeasterly winds generally continue into mid next week, with SCEC to borderline SCA conditions every afternoon on the bay and nearshore waters. && .CLIMATE... Issued at 316 AM CDT Fri May 16 2025 Both McAllen and Brownsville, including a 132 year record for Brownsville, high temperature records were tied yesterday. High temperatures this afternoon will also approach record temperatures. The daily record highest low temperatures also also be reached this Friday morning. High temperatures are forecast to be a degree or two lower for Saturday, but record high temperatures are still possible across the Rio Grande Valley Saturday afternoon. May 16th (Today) Record High Temperature / Highest Low Temperature Brownsville: 95 in 2024 / 81 in 2024 Harlingen: 97 in 2003 / 78 in 1999 McAllen: 100 in 2003 / 81 in 2024 May 17th (Saturday) Record High Temperature / Highest Low Temperature Brownsville: 96 in 1946 / 80 in 2017 Harlingen: 97 in 2018 / 79 in 1961 McAllen: 102 in 1946 / 81 in 2017 && .PRELIMINARY POINT TEMPS/POPS... BROWNSVILLE 79 92 78 92 / 0 0 0 0 HARLINGEN 77 96 77 95 / 0 0 0 0 MCALLEN 80 99 79 98 / 0 0 0 0 RIO GRANDE CITY 78 101 78 100 / 0 0 0 0 SOUTH PADRE ISLAND 78 84 79 85 / 0 0 0 0 BAYVIEW/PORT ISABEL 78 90 77 90 / 0 0 0 0 && .BRO WATCHES/WARNINGS/ADVISORIES... TX...None. GM...None. && $$ SHORT TERM...63-KC LONG TERM....56-Hallman AVIATION...69-HK ####018002503#### FXUS63 KGRR 161744 AFDGRR Area Forecast Discussion National Weather Service Grand Rapids MI 144 PM EDT Fri May 16 2025 .KEY MESSAGES... - Another round of thunderstorms Friday evening then fair and cooler into early next week. && .DISCUSSION... Issued at 252 AM EDT Fri May 16 2025 Severe storms have moved east and there will be a temporary lull in the weather until a second batch of storms arrives Friday evening, associated with a cold front trailing from the sfc cyclone tracking across the Michigan UP. Downburst winds will be the main threat, generally between 8 pm and 11 pm, with instability waning during the evening but impressive deep layer shear greater than 50 knots resulting in organized convection, mostly in the form of bowing line segments, but enough directional shear to allow for some rotating updrafts as well. Cooler, showery weather moves in behind the front for Saturday then a Canadian anticyclone builds in with fair weather into at least early next week. Good radiational cooling conditions Sunday and Monday nights could bring scattered frost with lows in the 30s across the northern zones. Rain chances return by mid-week although some model guidance suggest most of the precip remains south of Lower Michigan. && .AVIATION /18Z TAFS THROUGH 18Z SATURDAY/... Issued at 139 PM EDT Fri May 16 2025 Visible satellite loop shows cu developing across the region with high clouds streaming in from Wisconsin. Another round of showers/storms is expected to develop this evening in response to a wave of low pressure spinning around an upper low. Favored time frame is from 01z-05z. Gusty winds are the main threat with these storms and a few could be strong to severe. Once the storms pass through, we'll see ceilings fall to MVFR by sunrise. && .MARINE... Issued at 252 AM EDT Fri May 16 2025 No changes to the Small Craft Advisory. Winds and waves will be hazardous to small craft through Saturday evening and winds to 25 knots could persist into Sunday, though the trend will be for conditions to improve as high pressure builds in from the north early next week, with winds going off shore and waves decreasing. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...None. MARINE...Small Craft Advisory until 2 AM EDT Sunday for LMZ844>849. && $$ DISCUSSION...Ostuno AVIATION...04 MARINE...Ostuno ####018006488#### FXUS64 KTSA 161744 AFDTSA Area Forecast Discussion National Weather Service Tulsa OK 1244 PM CDT Fri May 16 2025 ...New AVIATION... .KEY MESSAGES... Issued at 255 AM CDT Thu May 15 2025 - Shower and thunderstorm chances for far eastern/southeast OK into northwest AR through mid afternoon today. - An unsettled weather pattern continues through the weekend and into early next week. Severe thunderstorms are expected at times. && .SHORT TERM... (The rest of today ) Issued at 1104 AM CDT Fri May 16 2025 Cold front extended across south central Oklahoma into northeast Oklahoma along a line from Okemah to Nowata and then into southeast Kansas. Ahead/east of this boundary low 70 deg dewpoints were expanding eastward through northwest Arkansas. Cloud cover moving into far northwest Arkansas has continued build over the past hour with radar echoes developing from Sequoyah co to Benton co. This development was moving into an unstable atmosphere with large amounts of surface & elevated instability and deep layer shear. Convection is expected to continue to increase in coverage as this activity quickly moves through far northwest Arkansas over the next couple of hours. Severe potentials have also increased over this area and it likely will not take much for storms to become strong/severe with large hail and damaging winds the main threats. Storm motions, like yesterday should be rather quick to the northeast with much of this convective development exiting the forecast area early afternoon as the frontal boundary continues its east southeast movement. Behind the cold front, dewpoints in the 50s to around 60 deg were reported with mostly clear skies. This clearing line should continue to move east southeast with the front as well and be located over southeast Oklahoma into west central Arkansas mid afternoon. Mostly clear conditions combined with westerly winds will help afternoon temps warm into the 80s for most locations. With the front across far southeast Oklahoma mid to late afternoon interacting with ample moisture and an unstable atmosphere, additional convection is forecast to develop. Current thinking is for storm initiation near the Red River into west central Arkansas. Much of this development looks to be near and just east of the CWA from Choctaw co to Franklin co. These storms should quickly move out of CWA and into southwest/central Arkansas by late afternoon/early evening. Again, increasing severe potentials will aid in large hail and damaging winds to be the primary threat. A very low tornado threat will also exist with the greater potential outside of the CWA. For the morning update, have adjusted PoPs and sky grids based on the mentioned above and also tweaked dewpoints to maintain the low 70 deg dewpoints ahead of the front. The rest of the forecast is trending well at this time. && .LONG TERM... (Tonight through Thursday) Issued at 255 AM CDT Fri May 16 2025 Drier air will push into the area for tonight into Saturday morning, with a lull in any thunderstorm activity through the morning hours on Saturday. This will be short lived however as moisture once again lifts back north in response to Lee cyclogenesis ahead of the main upper level storm system digging into the Desert Southwest. This will begin a period of increasing thunderstorm chances from Saturday afternoon through Monday and possibly into Tuesday. While the specific details are still to be determined and will be highly depended on previous days activity, expect periods of thunderstorms through the weekend as modest southwest flow aloft overspreads a seasonally moist and unstable airmass. Severe thunderstorms will be possible each day, with all hazards in play depending on timing and location of relevant features. As it stands now, thunderstorm chances will increase across eastern Oklahoma Saturday afternoon and evening as the warm front lifts northward. Another round of storms is expected into Sunday afternoon and evening as storms develop off a dryline over western/central Oklahoma. The main storm system begins to move into the Plains on Monday ,providing what is likely the most likely day to see more widespread severe thunderstorms across the region. Storms could linger into Tuesday as the slow moving trough axis slides through the area before departing to the east and pushing a rather strong cold front through the area. Cooler and drier air will filter in behind the frontal boundary with noticeably cooler temperatures progged for the rest of the work week. Lows could even dip into the 40s a couple of nights next week with highs mainly in the 70s. Low shower/storm chances enter the forecast again by the end of the week and into next weekend as northwest flow aloft strengthens over the Plains. Bowlan && .AVIATION... (18Z TAFS) Issued at 1244 PM CDT Fri May 16 2025 Scattered to broken mid and high clouds will continue to move east northeast this afternoon across southeast Oklahoma and northwest Arkansas ahead of a cold front moving through the region. Storm chances remain this afternoon ahead of the front, and will add a brief Prob30 group for KFSM. Behind the front, mostly clear to passing high clouds are expected this evening and tonight for the CWA. For Saturday morning, high level clouds are forecast to increase over the CWA along with moisture lifting into the region. There is potential for MVFR ceilings at KMLC/KFSM toward the end of the period. Storm chances Saturday look to be just outside of this TAF period. Winds start out breezy from the west and become variable tonight into Saturday. && .PRELIMINARY POINT TEMPS/POPS... TUL 87 57 83 64 / 0 0 20 50 FSM 89 62 89 68 / 20 0 30 50 MLC 88 61 86 68 / 10 0 40 30 BVO 85 51 80 60 / 0 0 10 60 FYV 85 55 85 63 / 40 0 20 60 BYV 84 56 84 61 / 50 0 10 60 MKO 86 58 85 64 / 10 0 30 50 MIO 83 53 80 61 / 10 0 10 70 F10 87 59 85 66 / 10 0 30 40 HHW 87 65 86 68 / 30 10 50 30 && .TSA WATCHES/WARNINGS/ADVISORIES... OK...None. AR...None. && $$ SHORT TERM...20 LONG TERM....04 AVIATION...20 ####018007032#### FXUS64 KSHV 161744 AFDSHV Area Forecast Discussion National Weather Service Shreveport LA 1244 PM CDT Fri May 16 2025 ...New AVIATION... .UPDATE... Issued at 1130 AM CDT Fri May 16 2025 Much of the region remains blanketed in cloud cover late this morning, but that is doing little to slow the warming process as most locations have already surged well into the 80s while dew points range from the lower to mid 70s. Suffice it to say the atmosphere isn't lacking in heat or moisture, and expect further destabilization through this afternoon with cap erosion gradually giving way to convective initiation across our NW zones by mid to late afternoon. This convection should further propagate SE over much of our NW half through the evening hours with severe storms possible during this late afternoon into early evening timeframe. Large hail and damaging winds remain the primary threats at this time and while the tornado threat is lower, it's not completely negligible in this late spring environment. Further details will be forthcoming with the afternoon forecast package, which should coincide closely with convective initiation later this afternoon. /19/ && .SHORT TERM... (Friday through Saturday) Issued at 323 AM CDT Fri May 16 2025 Main story in the short-term portion of the forecast revolves around the threat for strong to severe thunderstorms. Radar imagery is showing some thunderstorms ongoing across Arkansas early this morning with some light rain showers showing up across our far northern zones. Nothing to be too concerned about right now, but something to keep our eye on for sure. Our eyes will mainly be hyper focused on the threat of severe thunderstorms this afternoon. Very moist air will be in place across our region today with dewpoints in the lower to mid 70s. Storms will have a hard time developing through the early afternoon hours with some decent capping in place. However, as we move later into the afternoon and early evening hours this cap should begin to break as a mid-level jet moves eastward. As a result, thunderstorms will begin to develop across northeast Texas and southwest Oklahoma. Short range guidance is hit or miss on the exact location of the worst of the storms and how they continue into the evening. However, any storms that do develop should be capable of producing large hail and damaging winds with some very large hail in some of the more intense supercell structures. Because of this, we have a Slight Risk for severe thunderstorms painted across much of the area. Thunderstorms should diminish some heading into the overnight hours giving us a short break before our next round develops late Saturday afternoon and continues into the evening hours. Right now it looks like storms will develop initially along a dryline across north-central Texas that will congeal into an MCS as it moves east through our area. Typically with these types of systems, the initial threat will be for very large hail with any supercells that develop before it congeals into an MCS and then once this happens the main threat will transition to a wind threat across the area. I think there will be more of a tornado threat across far northeast Texas as storms initially develop as well, but this should diminish some as things start to take on the MCS form. That being said, can't ever rule out a tornado in these parts with any types of thunderstorms that move through. As for temperatures...it is going to be warm, muggy and uncomfortable through Saturday as our bodies try to adjust to the warmth again. /33/ && .LONG TERM... (Saturday Night through Friday) Issued at 323 AM CDT Fri May 16 2025 There remains some threat for strong to severe thunderstorms across the northern half of the forecast area on Sunday. That being said, trends are showing that the worst of the storms will be well to the west of our area, but we do remain in a Marginal Risk from SPC across the northern half for Sunday. Rinse and repeat for Monday and Tuesday, although at this timeframe, confidence becomes less on the strength and location of the thunderstorms, so we will need to continue to monitor the forecast for the potential of severe weather through the middle of the week. Our final system for the week looks to come on Tuesday night into Wednesday morning as a cold front moves through the area. This will bring us some cooler temperatures for the end of the week with highs returning to the 70s and 80s. Enjoy it while you can, it is only a matter of time before the unbearable heat returns. With all these chances of rain, the 7-day QPF amounts will be highest across northeast Texas, southeast Oklahoma and southwest Arkansas where some widespread 2-3 inches will be possible. With all this coming over the span of 4-5 days, there shouldn't be any widespread flooding concerns at this time. /33/ && .AVIATION... (18Z TAFS) Issued at 1235 PM CDT Fri May 16 2025 Regional sites are prevailing either VFR ceilings or high MVFR ceilings this period. MVFR sites should see lower ceilings scatter out over the next hour or so, leaving elevated overcast skies. The next 6 hours will have pretty consistent conditions. A near stationary cold front should begin to be an initiation point for showers and storms beginning around 17/00z, impacting KTXK and KTYR first. The storms should stay elevated as they move eastward over the next several hours, possibly impacting other terminals. Some of these storms may be severe, especially in areas along and north of the I-20 corridor. Surface winds will stay mostly southerly above 10kts through the afternoon and begin coming down in intensity overnight. Ceilings should stay VFR until beginning to fall again around 17/12z. MVFR ceilings are most likely, but a brief drop to high IFR levels can't be ruled out. /57/ && .SPOTTER INFORMATION STATEMENT... Issued at 1130 AM CDT Fri May 16 2025 Spotter activation may be needed late this afternoon through this evening, mainly along and north of the Interstate 20 corridor with any severe thunderstorms that develop. Similarly, timing of severe thunderstorms is likely late Saturday afternoon into the evening over much of the same area. && .PRELIMINARY POINT TEMPS/POPS... SHV 75 93 74 93 / 40 30 50 10 MLU 75 93 73 92 / 30 30 40 10 DEQ 64 87 67 86 / 30 30 60 30 TXK 70 91 71 90 / 40 40 60 20 ELD 69 91 70 91 / 50 30 60 20 TYR 72 90 72 91 / 40 40 40 10 GGG 72 91 72 92 / 40 30 50 10 LFK 74 94 73 93 / 10 10 10 0 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...None. LA...None. OK...None. TX...None. && $$ SHORT TERM...33 LONG TERM....33 AVIATION...57