Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 02/14/23

Area Forecast Discussion
National Weather Service Corpus Christi TX
541 PM CST Mon Feb 13 2023 ...New AVIATION... .SHORT TERM... (Tonight through Tuesday night) Issued at 347 PM CST Mon Feb 13 2023 Key Messages: - Warming trend continues through Tuesday. - Winds will continue to strengthen from the south-southeast through tonight. - Frequent gusts to Gale Force are expected late tonight through mid morning Tuesday from 20 to 60 nautical miles offshore. A few gusts to gale force will be possible across the bays and nearshore waters tonight. A deepening upper level low across the Desert SW will lift northeast across TX tonight, resulting in a strengthening southerly low level jet. Models vary between a 35 to 45 knot LLJ overnight. Some mixing will lead to breezy southerly winds across S TX overnight. The main concern is how much of that jet will mix over the bays and coastal waters. Since water temperatures are relatively cool in the upper 50s across the bays and nearshore waters, am not expecting too much mixing of the LLJ to the surface, but am expecting a few gusts to gale at times. The offshore waters are a bit warmer with SST near 70 degrees. The LLJ will also be ushering in warmer air temperature. Several models also show lapse rates across the coastal waters conducive for mixing. In addition, the HRRR indicated sustained winds around 30kts with gusts to 35-40kt across offshore waters. Probabilistic ensembles show a 50th percentile of 30kts or greater across the offshore water, as well. Given all of these factors, have issued a Gale Warning for tonight through mid morning Tuesday for the offshore waters. Small Craft Advisories are in effect for the bays and nearshore waters with occasional gusts to gale possible. The upper low will bring a dryline/frontal boundary across S TX Tuesday which will decrease wind speeds as it moves eastward through the day. The boundary is progged to reach near the coastline by late Tuesday morning or early Tuesday afternoon, then it washes out with a weak to moderate onshore flow returning to S TX by Tuesday night. There is a slight chance of showers tonight, mainly after midnight, across northern and eastern portions of S TX. PWATs are progged to increase to 1.2 inches across the northeast CWA. With the slightly deeper moisture, the strong LLJ could provide moisture convergence for a few showers to develop. A few showers continue Tuesday morning ahead of the dryline, then dry out from west to east. As onshore flow returns Tuesday night so does a slight chance of showers, mainly along the coast north of Rockport. && .LONG TERM... (Wednesday through next Sunday) Issued at 347 PM CST Mon Feb 13 2023 Key Messages: - Warm Temperatures in the 80s Wednesday afternoon - Cold front late Wednesday/Early Thursday - Elevated fire weather conditions Thursday - Cold temperatures and windchill below freezing Thursday night A mid-level trough will sweep across the Great Plains Thursday followed by weak ridging towards the end of the week and then quasi zonal flow Sunday. Sunday night a low dives south just off the CA coast then swings northeastward as it`s cross over the Baja peninsula with high pressure over the central Gulf resulting in southwest flow across South Texas. A cold front moves across the region Wednesday night into Thursday reaching the coast around 12Z. Strong winds across the inland areas will increase the risk of Elevated fire weather Thursday and very strong winds over the waters will lead to Small Craft Advisory conditions with gusts to gale possible. Afternoon temperatures ahead of the front on Wednesday will range in the 80s across the region followed by a 20-25 degree drop in high temps for Thursday. Overnight lows Thursday and Friday nights will dip into the mid to upper 30s with windchill in the mid 20s to mid 30s early Friday from the northern Coastal Bend to Victoria Crossroads and the northern Coastal Plains. Then high temperatures will warm over the weekend back to the mid 80s by Monday. Some Patchy sea fog will be possible Wednesday morning this week as dewpoints rise above SST`s by a few degrees. Isolated showers east will be accompanied by isolated showers and thunderstorms over the waters Thursday. The rest of the long term period is expected to be mainly dry and settled. && .AVIATION... (00Z TAFS) Issued at 531 PM CST Mon Feb 13 2023 VFR conditions and gusty winds this evening, but CIGS will gradually decrease through the night and all sites will likely see MVFR CIGS for a time late evening and overnight. Winds remain elevated at most sites with a 40-45kt LLJ above the surface. While wind shear criteria are not being met due to winds remaining elevated at the surface, expect a sharp increase in winds above the surface. A boundary moves through the area on Tuesday shifting winds to the west and northwest, still with strong gusts. VFR conditions return behind the boundary tomorrow as low clouds clear out leaving just some high clouds. && .MARINE... Issued at 347 PM CST Mon Feb 13 2023 A strong to very strong southerly flow is expected tonight. Occasional gusts to gale force will be possible across the bays and near shore waters with more frequent gusts to gale expected over the offshore waters. A Gale Warning is now in effect for the offshore waters tonight through Tuesday morning with Small Craft Advisories in effect for the bays and nearshore waters. The flow will weaken and shift to the southwest and west by Tuesday afternoon as a front moves into south Texas. Weak to moderate onshore flow is expected by Tuesday night. Weak to moderate onshore Wednesday will become very strong northerly flow after the front moves offshore Thursday morning. A Small Craft Advisory may be needed Thursday through the early evening hours on Friday with a few hours of Gale winds possible. Northeasterly flow becomes moderate late Friday then weak to moderate as winds shift back to onshore over the weekend. Patchy sea fog will be possible Wednesday morning followed by isolated showers and thunderstorms on Thursday. && .PRELIMINARY POINT TEMPS/POPS... Corpus Christi 64 80 58 81 / 10 10 10 0 Victoria 62 78 53 78 / 30 30 10 10 Laredo 59 83 57 89 / 0 0 0 0 Alice 62 82 53 86 / 10 0 10 10 Rockport 61 75 57 73 / 20 10 10 10 Cotulla 60 82 54 89 / 10 0 0 0 Kingsville 63 82 57 86 / 10 0 10 0 Navy Corpus 64 75 62 73 / 20 10 10 10 && .CRP WATCHES/WARNINGS/ADVISORIES... TX...None. GM...Small Craft Advisory until 9 AM CST Tuesday for GMZ231-232. Small Craft Advisory until 9 AM CST Tuesday for GMZ236-237. Small Craft Advisory until 6 PM CST Tuesday for GMZ250. Small Craft Advisory until 6 PM CST Tuesday for GMZ255. Small Craft Advisory until 9 PM CST this evening for GMZ270-275. Small Craft Advisory from 9 AM to 6 PM CST Tuesday for GMZ270- 275. Gale Warning from 9 PM this evening to 9 AM CST Tuesday for GMZ270-275. && $$ SHORT TERM...TE LONG TERM....BF AVIATION...PH/83
Area Forecast Discussion
National Weather Service Flagstaff AZ
256 PM MST Mon Feb 13 2023 .SYNOPSIS...Rain and snow showers develop this morning into the afternoon, especially along the Mogollon Rim. A much stronger storm system then brings much colder temperatures and strong winds for Tuesday and Wednesday, with periods of snow for nearly all of northern and central Arizona. && .DISCUSSION...through Tonight...An upper-level low continues to move across Arizona this afternoon. Scattered showers have developed across much of northern Arizona, with an area of banded precipitation across central Arizona. As the low tracks eastward through the day, the aforementioned band will continue to trek northeast along with increasing shower coverage across much of northern Arizona. Latest RAP guidance shows that the strongest frontogenetical forcing is expected to remain south and east of Flagstaff along the Mogollon Rim into the White Mountains. Thus, the heaviest precipitation this afternoon and evening is expected to over these areas. The current forecast has around 2-4 inches forecast above 6500 feet, with up to 4-8 inches possible in the heaviest snow. Additionally, with the cold-core of the low overhead, some embedded thunder may be possible. As the system moves into New Mexico, precipitation coverage and intensity begins to wind down, with only a few lingering showers expected through the overnight. Tuesday through Wednesday...Behind the first system, a stronger longwave trough begins to dig into the Great Basin. Moisture increases over the region, in addition to the remnant moisture from the previous system, which will allow for precipitation to develop starting Tuesday morning. Upslope-forced showers along the southward facing terrain look to be the initial areas to see snow. Later in the afternoon the main show begins as an intense band of heavy precipitation is then expected to move across the region from west to east through the afternoon into the overnight. 12Z HREF guidance has significant potential (~80% chance) for 1-2 inch/hour snowfall rates with this band over the higher terrain, especially from Flagstaff to Happy Jack to Forest Lakes. Very cold temperatures are expected with this system, which will allow for snow levels to fall down to around 3500 feet by Wednesday. Meaning that all but the lowest elevations of southern Yavapai and southern Gila Counties should expected to receive some accumulating snow. The greatest accumulations from this system, are expected to mainly be found above 6000 feet, where 6 to 12 inches are expected, with up to 18 inches possible in the heaviest snow. Lighter accumulations of 1 to 3 inches are expected for elevations between 3500 and 6000 feet. In addition to the snow, strong southwest winds 20-30 mph with gusts 45-55 mph are expected on Tuesday. The gusty winds and heavy snow will make travel even more difficult, with poor visibility in blowing and drifting snow. The wind will also make for very cold temperatures, with wind chills in the single digits over the higher terrain. Travel late Tuesday into early Wednesday across the High Country is STRONGLY DISCOURAGED. Heavy snow and blowing snow will reduce visibility on area roadways and lead to dangerous driving conditions. If you must travel, plan on snow covered roads and poor visibility. Be prepared for the potential to be stuck on area roadways for several hours. Wednesday Night through Friday...Dry, and cold northerly flow moves into the region behind the trough late Wednesday. Clearing skies, light winds, and a fresh snow pack will help temperatures plummet overnight into Thursday morning. Widespread single digits to below zero temperatures are expected across the high country, with much of the lower elevations dipping into the 20s. Additionally, wind chill values as low as -15 will be possible in any windier location over the high terrain Thursday morning. High pressure begins to build through the day Thursday, allowing temperatures to rise a bit over the previous day, however we remain cold. Saturday through Sunday...Continued dry conditions and gradually warming temperatures is expected through at least Saturday. Model guidance continues to hint at the potential for another system, late in the weekend as the ridge breaks down and a cut-off low forms off the West Coast. However, uncertainty remains high with this system, but nevertheless unsettled weather looks to potentially make a return again next week. && .AVIATION...For the 00Z TAF package...Expect local MVFR conditions in showers through 06Z along and south A KGCN-Four Corners line, primarily over the mountains. Winds generally southwest at 15-25 kts. After 06Z, a strong weather system will approach with the coverage of MVFR/IFR conditions and snow showers gradually increasing through Tuesday morning becoming widespread by midday Tuesday. In addition, southwest winds will strengthen, gusting to 45- 55 kts along and downwind of terrain features by early Tuesday morning. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER...Showers, mainly in the form of snow, becoming likely on Tuesday then lingering into early Wednesday. Southwest wind gusts in the 30 to 50 mph range on Tuesday shifting to lighter from the northwest on Wednesday. Cold both days. Thursday through Saturday...Look for dry conditions. Locally gusty northeasterly winds on Thursday and Friday will shift to southerly on Saturday. Cold on Thursday with a slight warmup on Friday and Saturday. && .FGZ WATCHES/WARNINGS/ADVISORIES... Winter Storm Warning from 6 AM Tuesday to 6 AM MST Wednesday for AZZ004-006>008-015-038. Winter Weather Advisory from 6 AM Tuesday to 6 AM MST Wednesday for AZZ005-012. Winter Storm Warning from noon Tuesday to 6 AM MST Wednesday for AZZ009>011-013-014-016>018-039-040. Winter Weather Advisory until 11 PM MST this evening for AZZ015>017. && $$ PUBLIC...Humphreys AVIATION...McCollum FIRE WEATHER...McCollum For Northern Arizona weather information visit
Area Forecast Discussion
National Weather Service Jacksonville FL
832 PM EST Mon Feb 13 2023 ...New UPDATE... .UPDATE... Issued at 825 PM EST Mon Feb 13 2023 Forecast remains on track with a slightly colder night in store. Just some high thin cirrus clouds tonight and light winds as an area of high pressure around 1018 mb over the eastern Gulf of Mexico pushes eastward into the forecast area overnight. Potential for patchy frost as lows dip to the mid and upper 30s inland and lower 40s closer to the coast. The HRRR and NAM models suggest some patchy fog for the Suwannee Valley area which could be more of an advective fog due to westerly flow off the Gulf of Mexico Monday afternoon, but model soundings and other guidance do not support it. In addition, airmass (00z JAX sounding PWAT 0.30 inches) just too dry to mention patches of fog at this time. For the marine forecast, very little change for the CWF update. && .NEAR TERM... Issued at 322 PM EST Mon Feb 13 2023 Dry weather, cool temperatures, and clear skies will continue through the rest of today and overnight as the influence of high pressure affects the southeastern US. Potential for frost development over inland southeast Georgia and portions of inland northeast Georgia. Overnight low temperatures will drop down into the 30s for inland areas and into the 40s along the coastline. && .SHORT TERM... (Tuesday through Wednesday) Issued at 322 PM EST Mon Feb 13 2023 High pressure conditions will continue to dominate weather conditions on Tuesday and Wednesday as high pressure ridging extends over the forecast area as the center of high pressure moves off towards the northeast. Prevailing flow will shift about to become more out of the southwest during this period resulting in increased moisture levels and cloud cover by Wednesday. High temperatures going into midweek will reach up into the 70s and lower 80s by Wednesday. Overnight low temperatures during this period will warm into the 50s by Wednesday. && .LONG TERM... (Thursday through Saturday) Issued at 322 PM EST Mon Feb 13 2023 Showers and possible thunderstorms will cross over the forecast area by the end of the week ahead of an advancing cold front moving in from out of the west. High pressure conditions will settle in over the region following the fropa bringing in dry weather, clearing skies, and breezy winds. Temperatures will be well above the seasonal average prior to the passage of the cold front at the end of the week and then drop to below average levels by the weekend as colder air settles in over the region. && .AVIATION... (00Z TAFS) Issued at 648 PM EST Mon Feb 13 2023 VFR with dry air and light flow over the region. Expect VFR to be persistent overnight over all sites with very light winds - possibly dropping to calm over some interior sites. Areas or widespread fog is not expected overnight due to very dry airmass despite strong radiational cooling. Hi-res models such as HRRR and RAP are suggesting patchy fog over some interior areas (especially Suwannee Valley/GNV area) briefly around sunrise. However, given dry airmass and NAM model soundings, confidence is not high enough to include in fcst. Very shallow and brief patchy fog cannot be ruled out late tonight and early Tuesday morning, however. Otherwise, some high clouds are expected to build from the west around mid to late morning Tuesday, but dry low levels are forecast to persist and therefore VFR. Sfc winds on Tuesday will initially be light easterly, becoming southeast 5-10 kt by around 17z-18z. && .MARINE... Issued at 322 PM EST Mon Feb 13 2023 High pressure will build overhead Tonight. The high will build more toward the east northeast Tuesday through Thursday. A cold front will move southeast across the area Thursday night into Friday. Advisory level conditions are forecast following the cold front. High pressure will build to the northwest Friday night, then north on Saturday. Rip Current Risk: Low risk of rip currents for area beaches today. Threat increases to moderate on Tuesday as winds shift to onshore. && .PRELIMINARY POINT TEMPS/POPS... AMG 37 71 49 78 / 0 0 0 0 SSI 44 66 54 73 / 0 0 0 0 JAX 38 72 52 80 / 0 0 0 0 SGJ 44 70 56 76 / 0 0 0 0 GNV 38 75 51 81 / 0 0 0 0 OCF 39 76 51 81 / 0 0 0 0 && .JAX WATCHES/WARNINGS/ADVISORIES... FL...None. GA...None. AM...None. && $$