Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 02/27/19

Area Forecast Discussion
National Weather Service La Crosse WI
946 PM CST Tue Feb 26 2019 .UPDATE...Tonight Issued at 946 PM CST Tue Feb 26 2019 Freezing drizzle was reported by law enforcement in Oelwein, Maynard, Lancaster, Platteville, and Prairie du Chien. RAP soundings show that there will be a loss of ice through much of the night. Due to this, issued a Winter Weather Advisory for Allamakee, Clayton, and Fayette counties in northeast Iowa and Crawford, Richland, and Grant counties in southwest Wisconsin through 7 AM Wednesday. A light glaze of ice is expected in these counties. && .SHORT TERM...(Tonight through Thursday) Issued at 232 PM CST Tue Feb 26 2019 Water Vapor imagery and RAP 500mb analysis showing a couple mid- level trough rotating through the Northern Plains/Upper Mississippi River Valley and through the Central Plains. Regional radar mosaic/surface observations showing pockets of light snow affecting the area. Snow will be on the increase later this afternoon into tonight as isentropic lift increases ahead of the incoming waves. Trough and forcing pushes east of the area by tomorrow morning with light snow rapidly tapering off from west to east by sunrise. Right now, looks like a general 2-5 inch snowfall for areas northeast of I- 94, highest amounts north of highway 10 in north central WI. Generally 1-2 inches expected elsewhere. Otherwise, look for much colder than normal temperatures tonight through tomorrow with lows in the single digits/teens and highs in the teens/lower 20s. Another round of much lighter snow or flurries will be seen late Wednesday night through Thursday mainly south of I-90 as active flow aloft brings another mid-level trough through the area. Doesn`t look like we`ll see more than a trace/dusting out of this. Staying colder than normal with highs Thursday only topping off in the upper teens to lower 20s. .LONG TERM...(Thursday Night through Tuesday) Issued at 232 PM CST Tue Feb 26 2019 The hits just keep coming as yet another much more vigorous mid- level/surface trough rotates through from the Plains Friday into Friday Night. Looks like generally 1-2 inches are likely out of this system. Arctic air then invades the area for this weekend into early next week. Record breaking lowest highs are on the line for Sunday and Monday as highs only top off in the single digits above and below zero. Overnight lows look to be in the teens below zero. Wind Chill headlines will also likely be needed Sat N/Sun Morn, Sun N/Monday Morn, and Mon N/Tuesday Morn. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday evening) Issued at 536 PM CST Tue Feb 26 2019 Short wave troughs will move southeast through northern and central Wisconsin and east through northern Iowa. The stronger of these 2 waves will be the northern one. At this time, only expecting maybe a dusting at the TAF sites tonight. MVFR ceilings will move into the TAF sites between 27.05z and 27.12z and be VFR for the remainder of Wednesday. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...Winter Weather Advisory until 7 AM CST Wednesday for WIZ054-055- 061. Winter Weather Advisory until 6 AM CST Wednesday for WIZ017-029. MN...None. IA...Winter Weather Advisory until 7 AM CST Wednesday for IAZ011-029- 030. && $$ UPDATE...Boyne SHORT TERM...DAS LONG TERM...DAS AVIATION...Boyne
Area Forecast Discussion
National Weather Service Denver/Boulder CO
833 PM MST Tue Feb 26 2019 .UPDATE... Issued at 751 PM MST Tue Feb 26 2019 Only minor changes were made to the forecast this evening as we wait to see how the low clouds and fog develop over the eastern plains and urban corridor. With dew points in the low 30s to upper 20s across the Denver metro, there is still medium to high confidence that the low clouds and fog will develop. A cold front moving over the Cheyenne Ridge this evening with much colder temperatures and stronger northeast winds behind it, will likely be the forcing that jumpstarts the low cloud and fog formation. The forecast has a mention of freezing fog late tonight into tomorrow morning across the majority of the urban corridor and eastern plains. Otherwise, the timing and POPs for the light snow showers over the mountains late tomorrow afternoon into tomorrow night look to be on track. && .SHORT TERM...(This evening through Wednesday) Issued at 252 PM MST Tue Feb 26 2019 Tonight another round of fog is expected to develop over the northeast plains near 11 PM. This will be due to another surge of moist, cool air with stable conditions and light winds. The HRRR depicts the boundary layer moisture oozing in near the Nebraska/Wyoming/Colorado boarder. The Denver Cyclone is expected to form overnight and advect fog towards Denver and the I-25 corridor late tonight. There will be a potential that flurries will form with the moisture and cold temperatures. The fog is not expected to dissipate until mid-morning. Based on the timing of fog formation yesterday and the mid-day dissipation today, you can expect to see similar progression. The Snow chances are expected to begin over the northern mountains around noon Wednesday, with coverage increasing later in the afternoon Wednesday. Snow will continue through Wednesday over the mountains. .LONG TERM...(Wednesday night through Tuesday) Issued at 252 PM MST Tue Feb 26 2019 A short wave ridge aloft will be over Colorado on Thursday. The flow aloft will be moderate and zonal. Pacific moisture will increase over the mountains in the afternoon, with light snow developing over most of the north central mountains in the afternoon. Across the northeast plains, a lee side surface trough will develop, with downslope warming along and west of the trough. Spatial cross-sections indicate low stratus/fog east of the surface trough, so warming may be more limited east of I-25 although there should be be some improvement. Thursday night through Friday, the flow aloft will continue to increase as a west to east subtropical jet move across the Great Basin/Four Corners region. The GFS20 had a 250 mb jet max over 150 kts by 12z Friday, then it lifts north and east across Colorado Friday afternoon and Friday night. The models show moderate mid and upper level QG ascent moving across the region at that time. In the mountains, the snow will increase in intensity late Thursday night and continue through Friday evening. Potential storm totals in this period range from 8 to 16 inches. Good orographics with enhanced banding/upright convection a concern. No highlights yet since most of this will occur in the late third to fourth and fifth periods, but a Winter Storm Watch a good possibility at that time. As far the the northeast plains are concerned, a cold front will push into the region from the northeast Friday afternoon, with a deepening northeasterly upslope in the afternoon and evening. If the cold air moves in sooner, than the evening commute on Friday could be a problem and snow showers increase. Over the weekend, it remain unsettled. The first system will exit the region Saturday morning, then another short wave trough embedded in the flow moves across northern Colorado. Another period of moderate to potentially heavy snowfall for the northern and central mountains Saturday night through midday Sunday. Across the northeast plains, much colder temperatures will remain in place with weak QG ascent in the mid levels. Should see some light snow for the urban corridor and northeast plains. A ridge of high pressure will move into the region early next week. The chance of snow will decrease in the mountains but cold air will remain entrenched over the northeast plains through Tuesday. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday evening) Issued at 751 PM MST Tue Feb 26 2019 Light winds will continue for the next few hours at the airports with mainly clear skies. Then, a surge of colder air will bring northeasterly winds, clouds and fog starting after 08Z-10Z. The exact start time of the low ceilings and visibilities is still unclear because the clouds haven`t developed over northeast Colorado yet. But with good low level moisture with dew points around 30 degrees lingering across the Denver metro, we are still fairly confident the low clouds and fog will develop at some point. So at this time, there wasn`t a need to change anything in the TAFs because nothing substantial has changed in our thinking. Once ceilings and visibilities improve late tomorrow morning, VFR conditions will take hold with light winds. && .BOU WATCHES/WARNINGS/ADVISORIES... None. && $$ UPDATE...Danielson SHORT TERM...Sullivan LONG TERM...Cooper AVIATION...Danielson
Area Forecast Discussion
National Weather Service Charleston SC
911 PM EST Tue Feb 26 2019 .SYNOPSIS... High pressure will continue to move offshore tonight. Then, a series of upper level disturbances will cross the region into the weekend, resulting in an unsettled pattern. A strong cold front could move through early next week. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... No major changes were made for the late evening update. The forecast is in good shape. Surface high pressure centered to the north will gradually shift offshore through the night. A weak return flow will develop as the weak coastal trough positioned just offshore dampens and quickly dissipates. Guidance shows several corridors of weak, multi-surface isentropic assent developing after midnight, but condensation pressure deficits remain high. This will help curtail shower development with most of the lift going towards lower cloud development. A band of enhanced lift with low condensation pressure deficits does look to develop just off the lower South Carolina coast early Wednesday with both the RAP and H3R with support from several other HREF members showing a band of isolated showers approaching the middle/upper Charleston County coast just before daybreak. Thick cirrus will persist aloft and area of high stratus/low altostratus forecast to propagate in from the southwest. This will result in a cloudy night with the thick cloud cover helping to keep temperatures up. Lows will range from the lower 50s across far interior Southeast South Carolina to the upper 50s across much of Southeast Georgia and extending into far south coastal South Carolina. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH FRIDAY/... Wednesday through Friday: Overall, the mid to late week time period looks unsettled with low confidence in forecast details. The pattern aloft will feature progressive nearly zonal flow with a few embedded shortwaves poised to cross the region. The first comes Wednesday, though most of this energy will remain south of the forecast area. The next will come Thursday and help to bring about the best chance for rain during this period. Then, finally, another is progged to come through Friday with what looks like another good shot of rainfall. Notable differences between models remain, and it`s difficult to put a whole lot of confidence in rain for any one particular period. The best chance still looks to come Thursday and that is where we have 70 percent rain chances across the entire area. For the entire period, rainfall amounts could be in the 0.50- 0.75 inch range, which would be beneficial given how dry it has been across the forecast area in the last 30 to 60 days. With no significant airmass change expected through the period, temperatures are forecast to run above normal. Highs are forecast in the upper 60s to low 70s each day with lows around the mid 50s. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... Low confidence this period as medium range guidance is not in great agreement. We leaned the forecast toward the 00Z/26 GFS, which WPC seems to favor. Periodic rain will likely linger through early next week as a cold front likely pushes through late in the weekend but upper forcing and lingering moisture keep some rain around, especially near the coast. Above normal temperatures should persist through at least Saturday, possibly into Sunday, with below normal temperatures the rest of the period as a much cooler air mass builds in from the north. && .AVIATION /02Z WEDNESDAY THROUGH SUNDAY/... VFR. Extended Aviation Outlook: Fog and stratus will be of concern each overnight period, with good chances of rain Thursday, Friday, and then late in the weekend. Periods of MVFR or IFR conditions will be possible at times. && .MARINE... Tonight: East/northeast winds with the coastal trough will gradually veer east to southeast overnight as the trough dampens and dissipates. Seas will range from 1 ft or less across the Charleston County waters to 1-3 ft over the remaining waters, highest over the Georgia offshore leg. Wednesday through Sunday: Overall, winds and seas are expected to remain well below Small Craft Advisory thresholds into the weekend. Winds will generally be less than 15 knots through Friday as weak systems pass through. Then late in the weekend a strong cold front could approach the waters, leading to increasing winds/seas. The main forecast challenge for the local waters will be the potential for fog beginning Wednesday night and continuing into the weekend. Confidence remains low at this point so it hasn`t been added explicitly to the forecast. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...None. SC...None. MARINE...None. && $$
Area Forecast Discussion
National Weather Service Duluth MN
738 PM CST Tue Feb 26 2019 .UPDATE... Issued at 738 PM CST Tue Feb 26 2019 Bumped up the pops to better represent where the snow is already falling. Bulk of the snow is falling under an area of frontogenesis at 700mb over northwest Wisconsin. Elsewhere, the snow is being driven by warm air advection. Rest of the forecast in the ballpark. && .SHORT TERM...(This evening through Wednesday) Issued at 225 PM CST Tue Feb 26 2019 The focus is on the expected snow through tonight. The main changes today are that the models have trended slower at moving in the snow from the south this afternoon, but increasing the precipitation and snow with the main round of snow that will move in from the west tonight. This forecast now has more snowfall than earlier than forecast, especially from east-central Minnesota into Northwest Wisconsin. This warranted adding Pine County and the northernmost tier of Wisconsin counties to the Winter Weather Advisory. There is surface high pressure centered over the Northland today. Despite the high pressure, the region already has cloudy skies. The forcing from a passing weak shortwave, combined with isentropic lift and a mid-level frontogenetical band, are contributing to this cloud cover, as well as causing light snow from central Minnesota into parts of northwest Wisconsin. This snow should slowly expand north into the southern forecast area this afternoon. Leaned on the latest RAP and HRRR runs to more accurately time this snow. However, there may be a break in the snow late this afternoon and this evening before more expansive and substantial snow develops tonight. A mid/upper level wave will move in from the west tonight, bringing stronger large-scale forcing for ascent. This wave will bring light to moderate snow to much of the Northland tonight through dawn. It now appears much of central MN to northwest WI can anticipate at least 2 to 3 inches of snow, and areas from Pine County east to Price County about 3 to 5 inches. There will be little to no wind with this snow, but slippery road conditions are expected, which will make for difficult travel conditions tonight. Overnight lows will primarily be near 0 or in the single digits below zero. The snow will diminish in northwest WI Wednesday morning. High pressure will build into the Northern and Central Plains from the west. There should be clearing skies across the Northland, and that sunshine will help boost temperatures to reach highs in the middle to upper teens. Some models, such as the 4 km NAM and NAM MOS are indicating highs in the lower 20s. This is certainly possible. It is a little difficult to forecast highs this time of the year for sunny days. The sun angle and length of daylight are increasing, so there is potential to underestimate just how strong the solar heating will affect temperatures. .LONG TERM...(Wednesday night through Tuesday) Issued at 225 PM CST Tue Feb 26 2019 A weak system crosses the forecast area on Friday night and may drop a few inches of snow across the southern half of the forecast area. This system will be fueled by a strong zonal jet and a vort max accompanying a mid-level shortwave. SREF ensembles try to bring higher QPF amounts northward, but these largely disagree with most other guidance. So have kept forecast more towards model means. After this system passes, the Northland will head into another arctic air mass for a prolonged period of cold weather. During this period, wind chill headlines are likely especially Sunday and Monday night where values head into the -40 F territory. Meanwhile temperatures fall into the -10 to -20 F range. Given the cold air mass precipitation will be limited by moisture availability. Despite putting small PoPs in along the South Shore for lake effect snow potential, the lake may largely be gelled up by this time which would make these superfluous. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday evening) Issued at 542 PM CST Tue Feb 26 2019 An area of light to moderate snow was moving past BRD/HYR at the start of the forecast and was in the vicinity of DLH. Cigs were in the MVFR/VFR range in the snow, with vsbys into the IFR/LIFR range in the more robust pockets of snow. This initial round of snow should push east of these terminals by 06Z. More light snow will arrive overnight and affect INL/HIB/DLH through about 12Z before ending. MVFR with this second round of light snow. All terminals will return to VFR by 15Z. && .PRELIMINARY POINT TEMPS/POPS... DLH -1 16 -2 20 / 100 30 0 0 INL -7 15 -2 20 / 70 0 20 10 BRD -5 14 -5 20 / 90 0 0 0 HYR 2 18 -5 22 / 100 50 0 0 ASX 2 18 -1 24 / 100 50 0 0 && .DLH WATCHES/WARNINGS/ADVISORIES... WI...Winter Weather Advisory until 6 AM CST Wednesday for WIZ006>009. Winter Weather Advisory until 6 AM CST Wednesday for WIZ001>004. MN...Winter Weather Advisory until 6 AM CST Wednesday for MNZ038. LS...None. && $$ UPDATE...GSF SHORT TERM...Grochocinski LONG TERM...Wolfe AVIATION...GSF
Area Forecast Discussion...UPDATED
National Weather Service Jackson MS
955 PM CST Tue Feb 26 2019 .UPDATE... Updated for evening discussion. && .DISCUSSION... Regional radars showed scattered storms tracking east between I-10 and HWY 84 just south of Natchez. This activity was being driven by a shortwave that will continue shifting east along the Gulf coast tonight. The storm activity will likely spread a little farther north into our southern zones with the eastward progression. The potential for any strong storms looks to remain south of our CWA. Have increased pops across the south but decreased pops across our central and northern zones the remainder of the night. Temperatures looked on track to dip into the 40s across the north with low to mid 50s elsewhere. /22/ Prior discussion below: Tonight & Wednesday: This evening will consist of some lingering showers that are ongoing across mainly zonal flow aloft over the region. Due to widespread lift in advance of an approaching shortwave, per GOES-16 water vapor (WV) imagery over Texas, this is helping some of the isentropic showers across the area. Most this is will gradually move through the area over the next couple of hours & lead to somewhat of a lull into early evening. In addition, temperatures have warmed pretty rapidly in the breaks in the clouds so have had to make some adjustments to the temperatures through this afternoon. For tonight, expect a weak shortwave to dive down through the area, bringing increasing lift & low-mid layer moisture across the area. In addition, most of the increasing juxtaposition of low- level moisture (i.e. dewpoints near 60 degrees or so) will reside along the Gulf Coast. As the shortwave trough dives through the Gulf Coast & warm front lifts north over the Gulf, expect increasing chances of showers & storms across the southern half of the area tonight. The best rain & storm chances will come across the Pine Belt & along & south of the Highway 84 corridor. Due to somewhat stronger mid- level flow & juxtaposition with some elevated instability, there remains some possibility of some more organized stronger convection in these areas. However, with run- to-run inconsistencies & better deep layer moisture off to the south, kept the "Marginal" risk out of the area for tonight. The newest HRRR & downscale NAM have somewhat trended north & also into our southwest, but just not confident in this airmass to receive much in the way of better organized convection. Due to widespread clouds & convection, lows will be above normal overnight. Expect another above normal warmth & scattered showers & some storms into tomorrow, but there could be a lull in the wake of the departing shortwave, leading to somewhat less coverage through midday. However, increasing lift & convergence from the warm front just to our south & cold front diving down towards our area to our northwest will help increase coverage of showers & storms to gradually increase again into the afternoon. Due to increasing low-level warmth & some isentropic subsidence through midday, this could help some breaks in clouds develop & another warm afternoon to develop. Highs should be around 5-7 degrees or so above normal, in the mid 60s in the northwest to low-mid 70s in the south. /DC/ Wednesday night through Monday: Zonal mid level flow pattern will keep the area unsettled through much of the period as embedded shortwaves rotate through. A weak cold front will attempt to move into the area Thursday, but weak upper support will allow the boundary to stall over northern sections and serve as a focus for a continuation of the expected showery weather. By Saturday, an initially shallow arctic airmass will begin moving into the area from the northwest. This will promote widespread mostly anafrontal precipitation as flow aloft continues from the west/southwest. May see some wintry precipitation Sunday night in the steadily deepening arctic airmass on the back side before the precipitation comes to an end, but what does manage to occur should be brief and light. Precipitation potential could turn back on again by Monday as mid/upper level flow tries to become southwesterly and a surface low develops in the western Gulf of Mexico. While moisture will have a hard time getting far to the north due to the cold advection/dry air in the lower levels, some wintry potential does look possible on where the northern edge of precipitation does set up. However, inconsistencies in model solutions at this time frame are maintaining low confidence in this outcome. /26/ && .AVIATION... 00Z TAF discussion: Local radar shows the isold -SHRAs have moved east of HBG and PIB but additional -SHRA and -TSRA development will remain possible across the south the evening. VFR conds wl prevail this evening but lower to MVFR from the south by 10Z. MVFR cigs wl prevail Wednesday but IFR cigs wl be psbl especially in the south Wednesday morning. Isold-sct -SHRA/-TSRA are expected south of HWY 82 Wednesday. /22/ && .PRELIMINARY POINT TEMPS/POPS... Jackson 51 72 57 70 / 25 40 63 56 Meridian 50 71 58 71 / 23 29 69 61 Vicksburg 51 70 56 69 / 32 39 56 50 Hattiesburg 54 74 61 73 / 63 40 54 63 Natchez 54 72 58 72 / 46 44 47 54 Greenville 47 65 53 65 / 14 34 57 44 Greenwood 48 67 53 65 / 10 37 66 47 && .JAN WATCHES/WARNINGS/ADVISORIES... MS...None. LA...None. AR...None. && $$ 22/DC/26
Area Forecast Discussion
National Weather Service Lake Charles LA
625 PM CST Tue Feb 26 2019 .AVIATION... Strong storms moving through southeast texas this evening. Copious amounts of lightning near the stronger storms. Ceilings will vary from 007 to 030. Showers noted along the se Tx cst and into sw La parishes this eve. All this actvty is moving to the east. Taf lctns varying from IFR/MVFR this eve but is xpcd to drop twrds sr. && .PREV DISCUSSION... /issued 401 PM CST Tue Feb 26 2019/ DISCUSSION... Guidance, and, therefore, the official forecast, has performed relatively poorly in identifying and expressing the relatively weak upper level features responsible for the precipitation (or lack thereof) over the last 36 hours. Much of the precipitation that was expected to develop earlier today has been delayed as a result of a slower than expected forward motion of an upper trof working it`s way across central Texas. The stronger convective activity associated with this trof is presently west of Houston and is expected to approach and move through southeast Texas and southwest Louisiana this evening into tonight. Therefore, will continue to carry likely PoPs through the night. Additionally, with weak high pressure at the surface sliding off to the east, winds will turn from easterly this evening to southeasterly by early tomorrow morning. The HRRR is very quick to develop marine fog as the winds begin to shift while the remaining short range guidance is a bit slower to do so. Still, with guidance in agreement on its eventual development, felt it prudent to insert patchy marine fog across the outer coastal waters beginning after midnight and approaching the coast during the early morning hours Wednesday. While it won`t be at all unusual for some of this marine fog to push inland along the coast, the light winds and very moist low level environment will potentially allow for some patchy fog development. This potential could be hindered by the scattered to numerous showers and thunderstorms expected to be moving across the region so forecast confidence in the inland fog is lower than the marine fog offshore. The upper level low will carry a good bit of the upper level moisture away with it as it departs on Wednesday which could leave a bit of a lull in the heavier rain. Still, enough low level moisture will remain in place from the surface to 8kft to allow for scattered, likely low topped, showers through much of the day. Upper level moisture returns late Wednesday evening along with another weak trof which will keep rain chances elevated Thursday. This trof will once again steal away the upper level moisture as it shifts east leaving another low topped isolated to scattered shower day on Friday. A big question mark remains with regards to the evolution of a cold front expected to push through the area sometime this weekend. The guidance remains spread on the frontal passage over a roughly 18 hour time frame from late Sunday night through mid Monday although this is actually a bit more clustered than the guidance was at this time yesterday. Widespread showers and thunderstorms are expected to precede the front with drier, significantly colder air expected to filter in behind it, but forecast confidence on timing is very low. The colder air moving in behind the front is expected to stick around for a few days as a large area of high pressure is expected to build across the central U.S. This is good news for Mardi Gras day festivities that were initially looking cold and wet. Now it appears that the cold will be the bigger concern as mostly clear skies should prevail. Jones MARINE... Modest east winds along with scattered showers and thunderstorms will continue through the night with increasing chances of sea fog formation beginning early Wednesday morning. Winds will gradually become more southeasterly during the day Wednesday with an onshore flow expected to persist the rest of the week. Showers and isolated thunderstorms are expected for most of this upcoming week due to a series of upper level disturbances moving across the region. Patchy to areas of fog will be possible through Friday. && .PRELIMINARY POINT TEMPS/POPS... AEX 53 72 60 74 / 50 60 40 50 LCH 59 73 64 73 / 70 60 30 60 LFT 58 73 64 74 / 70 70 40 60 BPT 60 73 64 74 / 80 40 30 50 && .LCH WATCHES/WARNINGS/ADVISORIES... LA...None. TX...None. GM...None. && $$ AVIATION...19
Area Forecast Discussion
National Weather Service Miami FL
820 PM EST Tue Feb 26 2019 .UPDATE... Scattered to numerous showers and a few thunderstorms are impacting South Florida this evening, and especially across the northern half of the area, this activity may continue overnight. Where there are breaks in the showers, particularly over western interior areas, at least patchy fog is likely to develop, and the potential for dense fog will be monitored. Heaviest localized rainfall amounts of 1 to 2 inches are possible but most areas will receive much less. Temperatures in the 70s as of 8pm will only fall 5-10 degrees by sunrise, as above normal warmth continues. && .PREV DISCUSSION... /issued 658 PM EST Tue Feb 26 2019/ AVIATION... Rain and numerous showers will continue across the region throughout the evening until around 04Z for KFLL, KPBI, AND KFXE and around 07-08Z for KAPF, KOPF, KMIA, AND KTMB. An isolated TSTM is also possible along with localized MVFR conditions. Fog may be a concern for KAPF for early Wednesday morning due to residual moisture, but confidence is not high enough to include in TAF at this time. Otherwise, prevailing VFR conditions are expected. A gradual veering of winds from E to SW are expected Wednesday afternoon. PREV DISCUSSION... /issued 349 PM EST Tue Feb 26 2019/ DISCUSSION... SHORT TERM (Tonight through Thursday night) Showers have been slow to develop today, leading to of course lower overall rainfall coverage but also breaks in clouds, allowing temperatures to rise into the low to mid 80s across the region. Instability is thus relatively high, and any showers that do (and are) develop(ing) will be convective in nature with a threat of frequent lightning. Actual warm frontal boundary that should be the focus for shower activity today is a bit diffuse but appears to be located mainly just north of Interstate 75, cutting across the heart of the CWA. Through the evening, this feature will drift northward. HRRR and other mesoscale guidance (though has been over-predicting coverage through today) suggest convection will increase in areal size and intensity through at least early evening, so rain chances remain relatively high through sunset. Cant rule out locally heavy rainfall, but this will not be realized in most locations. Activity should diurnally wane, then reinvigorate Wednesday due to modest instability and very high moisture levels. With southwesterly flow on the south side of the warm front, focus for rainfall Wednesday afternoon should be over northeastern areas of the CWA, especially as a subtle perturbation in the H5 flow crosses north of the region during the afternoon. Behind this feature, the front will continue to lift northward, taking the deepest moisture with it, and dry air will settle in by Thursday. Temperatures will remain above normal in the short term, with maxima in the low to mid 80s and minima in the 60s interior and west, low 70s across the east coast urban areas. LONG TERM (Friday through Monday night) Upper level flow remains zonal and progressive, with a series of weak impulses riding the southern jet stream across the Southeast CONUS. However, low-level western Atlantic ridging will remain strong, likely keeping any disturbed weather to our north through much of the extended. Some of the global model guidance suggests a cold front may approach from the north late in the period, so maintained the model consensus blended PoPs then. Still plenty of uncertainty this far out however. Temperatures will remain on the warm side, with above normal values likely into the weekend. MARINE... East wind 20 knots and seas of 6 to 8 feet for waters off Palm Beach warrant a Small Craft Advisory through 1 AM EST, elsewhere mariners should use caution. As a warm front lifts north of the waters tonight, wind will shift southerly and diminish in intensity. This will improve marine conditions. Southwest wind at 10 to 15 knots will prevail Wednesday and Thursday. Isolated to scattered thunderstorms are expected through Wednesday evening, especially over northern Atlantic waters. BEACH FORECAST... High risk of rip currents remains in effect for Atlantic beaches until sunset. Lessening wind speed and direction veering to the southwest will improve conditions Wednesday, but the residual effects from early wind strong onshore flow will likely lead to a moderate risk on Atlantic beaches, with further improvement on Thursday. && .PRELIMINARY POINT TEMPS/POPS... West Palm Beach 69 83 65 84 / 50 60 20 10 Fort Lauderdale 71 84 68 84 / 50 60 20 10 Miami 70 85 68 86 / 50 60 10 10 Naples 67 83 67 82 / 50 30 0 10 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...None. AM...Small Craft Advisory until 1 AM EST Wednesday for AMZ650-670. GM...None. && UPDATE...23/SBK DISCUSSION...23/SBK MARINE...23/SBK AVIATION...03/Fell BEACH FORECAST...23/SBK