Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 04/01/25


Area Forecast Discussion
National Weather Service Denver/Boulder CO
808 PM MDT Mon Mar 31 2025 .KEY MESSAGES... - Widespread alpine snow developing tonight and continuing through Tuesday night. - Showers and windy conditions across lower elevations Tuesday. - Another chance of snow Wednesday night through Thursday night with some rain mixing in on the plains. There is a low chance that this system produces accumulating snow with travel impacts on the plains. - More significant precipitation still possible around Saturday, but chances of heavy precipitation or significant snow are decreasing. && .UPDATE... Issued at 807 PM MDT Mon Mar 31 2025 WSW flow will continue overnight. Cross-sections show an increase in moisture, in the nrn mtns after midnight, with WSW flow favoring the Park Range and wrn areas of zn 33 for heavier snow. Otherwise there will be periods of lighter snow in other mtn areas. Across the plains, there have been some strong storms north of the CO-NE border. These have been moving eastward and have shown no sign of developing further southward. Thus will only mention low pops over the far nern plains thru midnight. && .SHORT TERM /Through Tuesday/... Issued at 240 PM MDT Mon Mar 31 2025 Water vapor satellite imagery showing a closed low off the Oregon and northern California coast with strong westerly flow aloft across the intermountain west. This will spread moist eastward across the Rockies tonight and Tuesday. For Colorado, moisture increases tonight in the west-southwest flow aloft bringing widespread mountain snow. Steep lapse rates of 7-9(C/km) up to 400mb and the left exit region of the jet will slide across the region. Snowfall amounts of 8 to 14 inches are expected, with locally heavier amounts possible if we end up with banded snowfall. One thing working against heavier snowfall is the west- southwest flow aloft through Tuesday morning. Upper level pattern gets messy Tuesday with broad troughiness across the Great Basin and Rockies. Models show a new closed low forming over Montana and northern Wyoming Tuesday with troughiness extending south through eastern Colorado. At the surface, cold front tracks southward late Tuesday morning and afternoon. For the urban corridor and eastern plains, models vary greatly on the cold front. The ECMWF shows a well defined northerly push for late morning and afternoon with rain showers, possibly mixing/changing to snow late in the day. At the other end of the spectrum, the HRRR model washes out the cold front with gusty westerly downslope winds prevailing through the day leading to dry conditions. Leaning heavily towards the ECMWF. The HRRR has a history of over mixing this type of westerly flow, Also, the GFS is somewhat similar to the ECMWF, so wouldn`t be surprised to see numerous showers over the Denver area and parts of the plains. As far as high winds and high fire danger goes, expect the worst conditions to be over southeast Colorado. Southern Lincoln County approaches red flag criteria, but widespread red flag conditions are expected to fall short of being met as the cold front brings higher humidities mid to late afternoon. && .LONG TERM /Tuesday night through Monday/... Issued at 340 PM MDT Mon Mar 31 2025 A shortwave trough will be moving out of our forecast area on Wednesday which will lead to brief subsident flow. This will put an end to the showers for the most part across the plains and foothills. Some light snow showers will continue in the mountains with minimal amounts. Temperatures will be cooler than normal as cold air aloft stays overhead. Models have gotten more interesting for Thursday with respect to the strength of a shortwave trough. Some models, especially the GFS, have this shortwave much stronger than previous runs and it is possible that up to 40 knots of easterly winds develop at 700 mb. The GFS ensemble members with the strong easterly winds, along with warm air advection, have significant snow on the plains with a third of the members producing over 8" of snow for Denver. So it now appears Thursday will need to be watched closely because there exists a small chance for a relatively significant snowfall. PoPs, QPF, and snow amounts were increased on Thursday for much of our forecast area. The most likely scenario is a trace to 3 inches across the Denver metro and plains while 2-6" is possible over the Palmer Divide. There will be a brief break in the precipitation during the day on Friday as the shortwave that produces snow over our area on Thursday moves out of the area. There will be some moderation in temperatures with highs near 50 in Denver but that is still well below normal. Models are coming into better agreement for the Friday night through Saturday night system. A ridge off the southeast US coast will stall a large shortwave trough over Arizona on Friday. Models then have this shortwave trough weakening as it moves eastward and this is the reason the chance for a significant storm continues to decrease. Having said that, Friday and into Saturday, a cold front will move across the northeast plains of Colorado with moderate northeast, upslope winds behind it. This, along with healthy moisture in the area, will combine to create high coverage of snow across our forecast area. The foothills and Palmer Divide will see the highest snowfall totals in this event due to upslope flow. Snow amounts in the 6-12" range could occur in those areas through Saturday night. The I-25 corridor will see lighter amounts but travel could be impacted especially Saturday morning. Very little snow may fall over the far northeast plains as temperatures will be warmer with much less overall precipitation falling there. High PoPs in the 70-80 percent range are in the forecast for most of the forecast area Friday night and Saturday morning. There will be a warming and drying trend Sunday through the middle of next week. && .AVIATION /00Z TAFS through 00Z Wednesday/... Issued at 513 PM MDT Mon Mar 31 2025 A few boundaries moved across DIA this aftn which have led to chaotic directions. Winds have gone more NW and should stay that way thru 01z. Radar shows srn part of boundary has stalled and may eventually move back north. This could lead to a more S or SE wind between 01z and 02z but confidence is low. At any rate winds should transition to SSW by 06z. On Tue, SW winds will increase by 13z and then turn more W or WNW by 18Z. Gusts from 30-35 mph will be possible by 18z. In the aftn, a band of showers may move across by 21z with winds become more NW. Gusts to 30-35 mph will continue thru 00z. Ceilings may drop down to 4000-5000 ft if band of showers do come across in the aftn. && .BOU WATCHES/WARNINGS/ADVISORIES... Winter Weather Advisory until 6 AM MDT Wednesday for COZ031-033- 034. && $$ UPDATE...RPK SHORT TERM...Meier LONG TERM...Danielson AVIATION...RPK
Area Forecast Discussion
National Weather Service Cheyenne WY
936 PM MDT Mon Mar 31 2025 .KEY MESSAGES... - Showers with a few thunderstorms will move over the High Plains through this evening and may produce isolated small, soft hail. - Rain showers will change to snow by early evening in Carbon county, with multiple rounds of snow showers expected through Tuesday morning. Some snow showers will be locally intense, producing low visibility and slick conditions along I-80. - Moisture wrapping back into the area may produce slushy snow accumulations along the US-20 corridor Tuesday evening through Wednesday morning, but confidence is fairly low. - Strong to locally high winds return to the area Tuesday and Wednesday. - Cold end to the week and start to the weekend, with a warming trend expected to start next week. && .SHORT TERM /THROUGH WEDNESDAY NIGHT/... Issued at 402 PM MDT Mon Mar 31 2025 Spring is surely in the air today with thunderstorms, snow, and wind all in the forecast somewhere in our area over the next few days. A broad trough encompassing much of the western CONUS this week will keep an unsettled weather pattern in place. While the main trough axis is still off of the West coast, a powerful Pacific jet stream is surging inland across the Great Basin and along the WY/CO border. Current mesoanalysis shows moist isentropic lift in place across much of the area, which is helping to kick off another round of shower activity this afternoon. With upwards of 500 J/kg SBCAPE in place across far southeast Wyoming and the addition of added lift from a synoptically forced Chugwater cyclone convergence zone, some of these showers are producing lightning. Very low freezing levels will make it pretty easy to get small hail out of any convective showers or thunderstorms today, but it will probably be of the softer variety. Expect this activity to grow increase in coverage over Goshen & Niobrara counties, and then spread into the central and northern Nebraska panhandle. Activity is also expected to fill in further west (Converse & Carbon) ahead of the frontal boundary currently straddling across central Wyoming. Modest convective instability and very steep lapse rates are also present in this area, and precipitation should quickly flip over to snow once it begins. Therefore, locally intense banded snowfall can be expected along and ahead of the frontal boundary through about the middle of the evening hours. We will need to monitor for short-fused hazard potential. While snow accumulations are not expected to be significant on the roadways, significant visibility drops and crashing temperatures could still cause short term problems. This activity, and the showers over the High Plains, should continue until the frontal boundary clears the area a little before midnight. After a short break, strong isentropic lift will pick up again after about midnight across Carbon county ahead of another stronger cold front which will follow a more obvious upper level shortwave trough axis. While this activity will be more stratiform rather than convective, models are showing a region of frontogenesis developing along the lifting northeastward just on the fringe of a strengthening surface/lower atmosphere low pressure center. Hi-res models are depicting the potential for upwards of 0.5" liquid precipitation under the frontogenesis band. While the warm antecedent conditions will make accumulations difficult, especially on the road, the potential for heavier rates and largely overnight timing may still lead to some difficult travel conditions. Therefore, decided to expand the Winter Weather Advisory to central and northern Carbon county, starting this afternoon to cover the first frontal passage, and continuing through Tuesday morning to cover the second phase too. Most snow amounts will probably be in the 1 to 4" range, but locally higher amounts and the potential for very low visibility is enough to nudge to an advisory. Tuesday will be another messy day across the area. Lee cyclogenesis is expected tonight across the High Plains, and a strong surface cyclone will wrap up and lift northeastward through the day Tuesday. While most guidance shows this low pressure center developing over northeast Colorado and lifting into southwest Nebraska, there are a few outlier models (e.g. RAP and HRRR) which show the surface low centered near the North Platte River Valley. This is notable because the outlier case would lead to the development of a westerly sting jet across the I-80 corridor Tuesday morning and significantly increase the potential for high winds. While worth mentioning, this remains an outlier, and nearly all LREF members keep the low pressure center to our south, thus leading to a more NW wind orientation, and overall lighter speeds. Even in the lighter wind scenario though, it will be a pretty windy day across the entire area with temperatures slightly below seasonal averages. By Tuesday evening, the cyclone will be moving across central South Dakota, but it will have a very large circulation. As a result, moisture may begin to wrap back into our northern areas Tuesday afternoon through Wednesday morning. Overall ensemble spread depicts roughly a 30% probability of 0.25"+ liquid precipitation along the US-20 corridor from Douglas to Chadron, with a few outlier members showing over 0.75" or more. For now, the forecast favors the median solution which is modest precipitation (mostly wet snow) Tuesday night into Wednesday leading to about 1 to 4" of slushy accumulation in the US-20 corridor through midday Wednesday. The tight pressure gradient remaining over the area will also increase the probabilities of high winds for the wind prone areas (particularly the I-80 summit) Tuesday night into Wednesday morning. This messy storm should finally depart Wednesday afternoon, bringing a short break into early Thursday. && .LONG TERM /THURSDAY THROUGH MONDAY/... Issued at 402 PM MDT Mon Mar 31 2025 The long term begins active as we see more rounds of precipitation moving across the region, though models continue to tone down expected QPF amounts with the bulk of accumulation further to our south. Still, some appreciable rain and snow will be possible, primarily impacting our southern and eastern zones, through the end of the week, with a warming trend moving late into the weekend and into the extended forecast. Thursday begins with a broad upper-level trough over the majority of the Western US, with this system expected to tighten up and form into a more consolidated trough through Friday, including a closed upper-low in the Desert Southwest, before then slowly sliding eastwards over the course of the weekend, allowing a transitory ridge to then take its place to start next week. At the surface, we should see a pair of shortwaves moving across the region on Thursday and Friday, with a strong high descending from Canada and overtaking the Western US by late in the weekend. Under this pattern, we can expect to see a couple of rounds of QPF on Thursday and again Friday from these passing shortwaves, but with the strongest forcing and more plentiful moisture further south of the region, significant accumulations will be unlikely with each of these systems. NBM probabilities for snow have seen quite the reduction since this weekend, with 24-hour accumulations of 1 inch or more at only 25-40% for our southern zones outside of the mountains, and only slightly better for Friday as by Saturday morning we see a more widespread 30-50% of once again 1+ inch for a 24-hour period, primarily for Laramie and Albany Counties. And with any snow that does fall, warm ground temperatures should preclude much in the way of total accumulations. Otherwise, overall QPF amounts stay on the lighter side, less than 0.2 inch outside of the mountains, so the chance of heavy precipitation in any case is unlikely. Meanwhile these systems will bring a fresh batch of cold continental air from up north, bottoming out on Saturday with widespread highs in the 30`s to 40`s and sub-freezing lows in the teens to low 20`s. But as the ridging begins to overtake again this weekend, we`ll see a pretty quick turnaround, and should be expecting widespread 60`s once again to start next week. && .AVIATION /06Z TAFS THROUGH 06Z WEDNESDAY/... Issued at 928 PM MDT Mon Mar 31 2025 Southwest flow aloft will turn west on Tuesday as a cold front moves across the terminals. Wyoming TAFS...For Rawlins, ceilings will range from 800 to 2500 feet until 12Z, with light snow reducing visibilities to 3/4 to 4 miles, then ceilings will improve to 4000 to 10000 feet. Winds will gust to 30 knots from 12Z to 00Z. For Laramie and Cheyenne, ceilings will range from 5000 to 9000 feet. Winds will gust to 35 knots at Cheyenne after 15Z Tuesday, and to 32 knots at Laramie from 15Z to 00Z. Nebraska TAFS...Ceilings will lower to 1500 feet through 15Z, with fog reducing visibilities to 1 to 3 miles, then ceilings will improve to 3500 to 10000 feet after 15Z, except for light rain and fog at Chadron and Alliance after 00Z, reducing visibilities to 3 miles and ceilings to 2500 feet. Winds will gust to 25 knots at Sidney until 09Z, and after 00Z. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...Winter Weather Advisory until 8 AM MDT Tuesday for WYZ104-105- 109-110. Winter Weather Advisory until 6 PM MDT Tuesday for WYZ112-114. NE...None. && $$ SHORT TERM...MN LONG TERM...CG AVIATION...RUBIN
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
1051 PM CDT Mon Mar 31 2025 ...Updated 06z Aviation... .KEY MESSAGES... - Strong to severe storms expected Tuesday night into Wednesday. Damaging winds, large hail, and heavy rainfall are the most likely hazards. Tornadoes are also possible. - Gusty winds around 30-40 mph return Tuesday morning continuing through the afternoon. Isolated gusts above 45 mph are possible. && .DISCUSSION... Issued at 323 PM CDT Mon Mar 31 2025 There is a lot to unpack with the forecast, so let`s start with the more clear cut aspects. This afternoon is going to be fairly quiet and cool with highs around the area reaching into the low to mid 50s thanks to a boost from solar heating as clouds continue clearing out this afternoon. A very strong LLJ forms across the central CONUS overnight tonight into Tuesday morning. This jet stretches from West Texas all the way into southern Saskatchewan. Simultaneously, a large 500mb trough traverses to the the leeward side of the northern Rockies with a southern jet streak whose exit region dumps straight into western KS and OK. This helps spin up a lee trough that deepens through the morning Tuesday. While all of this is occurring across eastern CO and western KS, the 850mb jet sets up across eastern KS into western MO. Unimpeded mixing from the base of this jet to the surface will result in another day of gusty winds. Gusts around 35- 40 mph are possible with the potential for some isolated gusts over 45 mph are possible. It certainly poses the question of if a Wind Advisory through the afternoon is needed. At this current juncture, widespread, frequent 45+ mph gusts should be more concentrated west of the area with the frequency of 45+ mph gusts in our region being much less. This wide wind field also results in warm air and moisture being vaulted into the region. Highs Tuesday increase 10-15 degrees into the mid 60s to near 70. More importantly dew points soar almost 25- 30 degrees from sunrise until midnight Tuesday into Wednesday. This creates a fairly unstable environment across central and eastern KS Tuesday afternoon. This is where things become a little more complex. Cold frontogenesis as well as a dryline act as a catalyst for convection Tuesday evening across central and eastern KS. Timing of convective initiation looks to be around 7-9 PM. Further accelerated southerly flow ahead of these boundaries sharpens the temperature and moisture gradient maintaining storms. CAM guidance points toward a rather robust line of convection making its way through the region entering far NW MO around 10-11 PM, reaching the KC metro around 12-2 AM WED, and marching through Sedalia and Kirksville around 3-5 AM. Damaging winds and large hail remain the primary hazards. Confidence is fairly high in these hazards. MUCAPE exceeding 1500 J/kg, DCAPE nearing 800 J/kg, and lapse rates around 7-8 C/km bring about decent convective parameters for large hail (potentially up to 2 inches) and damaging winds (possibly 70+ mph). Vertical profiles and hodographs show ample shear and helicity especially in the lowest 3 km. Where things become more uncertain is the overall environment ahead of the storms system and how it will change after sunset. It will be a race between nocturnal cooling and warm air advection. This will play a crucial role in the low level environment. After sunset, the low layers cool off forming an inversion and generally decoupling from the surface. This effectively causes cloud bases to rise above the inversion creating elevated storms. However, warm air advection ahead of the storms may warm the low layers just enough for storms to remain surface based. This could increase the potential for stronger storms and tornadoes as surface based storms would be able to tap into the notably sheared low level environment indicated by model 0-3 km hodographs. Looking at CAM members which specifically maintain that surface based connection shows a large QLCS structure. The most recent run of the HRRR also shows the potential for leading supercells which is increasingly concerning for all severe weather hazards. However, model vertical profiles also keep the generally high based storm environment. These profiles also show WAA potentially maintaining the CAP reducing the chances for storms to return to surface based. Unfortunately, we will not get a clear picture of how these storms might behave until after they have formed in central KS. Fortunately, there should be ample amount of time to see how storms will interact with the environment before they arrive on our doorstep. It is important to note that the uncertainty in surface versus elevated storms does not affect the potential for damaging winds and large hail. Another potential hazard that is often overlooked is heavy rainfall. Guidance is suggesting PWAT values around 1.1-1.5 inches indicating the potential for heavy downpours. 1-hour flash flood guidance sits around 1.2-1.5 inches meaning that an excessively heavy downpour could lead to localized flooding issues. Right now that threat for flooding hazards remains relatively low compared to the wind and hail; however, it should not be overlooked. It is imperative that you have multiple methods for receiving weather alerts during the overnight hours. The day Wednesday once again looks to be warm and breezy. The dry air behind the storms decreases cloud coverage and enables temperatures to rise into the 60s and 70s. Beyond Wednesday, another substantial synoptic low moves into the SW CONUS. This ejects several shortwave across the CONUS which compete with a midlevel high that settles across the the northern CONUS. This has been pushing rain potential in and out of the region for the next several days. Model runs have been rather divergent bringing ran into and out of the region flipping about depending on which sinusoidal pattern it chooses to run with. We will dig into this pattern evolution after dealing with the storm system on deck. && .AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/... Issued at 1047 PM CDT Mon Mar 31 2025 Strong system starts to move toward the area Tuesday afternoon and evening. Expecting stronger southwesterly wind gusts through the afternoon and most of the evening. Ceilings will develop ahead of the front but expecting most bases to be VFR. A few isolated showers and thunderstorms are possible, therefore, have placed the PROB30 groups toward the end of the TAFs, but the bulk of the activity along the cold front may be after 06z during the early morning hours of Wednesday. && .EAX WATCHES/WARNINGS/ADVISORIES... MO...None. KS...None. && $$ DISCUSSION...Pesel AVIATION...Krull
Area Forecast Discussion
National Weather Service Miami FL
800 PM EDT Mon Mar 31 2025 ...New UPDATE, AVIATION... .UPDATE... Issued at 747 PM EDT Mon Mar 31 2025 Late afternoon convection is still affecting portions of central/eastern Palm Beach, and metro areas of south Broward/northern Miami-Dade counties. LPMM and High-Res short term data suggest these cells could linger through around 9-10pm while slowly dissipating. Thus, POP/Wx grids have been updated to reflect this longer timeframe for these cells to last. Rainfall estimates of 2-3 inches have prompted a Flood advisory for the Miramar area, including US-27, with additional 1 or 2 inches possible during the next hour or so. Rest of the forecast package remains on track and no further updates are required attm. Expect another mild evening and overnight hours with lows in the mid-upper 60s inland, and in the low 70s near the coast. && .SHORT TERM... (Rest of today through Tuesday) Issued at 1204 PM EDT Mon Mar 31 2025 GOES Imagery early this afternoon depicts cloud streets of shallow capped cumulus clouds reminiscent of summer time across South Florida. The discussion & forecast from the midnight shift remains on track with the potential of a few strong to marginally severe storms this afternoon across the eastern half of the area. Mesoscale models such as the HRRR and RAP have been fickle and unrepresentative for our region over the last several days. However, more dry air in the vertical column should indeed limit convective coverage compared to what unfolded yesterday. Rain chances remain at a modest 30-40% along the east coast of SoFlo with lower values west of Lake Okeechobee. Forecast parameters such as DCAPE 1100+ J/kg, SBCAPE of 2000-3000+ J/Kg, and steep low level lapse rates support the threat of some robust storm activity once the capping inversion erodes even though 500mb temperatures are a few degrees warmer than yesterday. If a taller core does develops, DCAPE and dry mid- level air may allow for strong to severe downbursts (& wind gusts) to occur. 500mb temperatures of - 9C to -10C could still support the potential of small hail with the most robust cores. In addition, light southwesterly 850mb flow may pin the Atlantic sea- breeze along the coast. While models depict convective initiation occurring late (4-6pm) in the afternoon with the sea- breeze making further progress inland, variations in this evolution may support a non- zero (<2%) conditional tornado risk as a corridor of enhanced bulk shear and SRH materializes on the stable side of the sea-breeze boundary. The best dynamics given the flow regime for this would be across Palm Beach County and northern Broward County. HREF`s LPMM also hints at the potential of a few localized swaths of 1-2" of rainfall with afternoon thunderstorms today. This could materialize if a storm is pinned along a boundary as mid-level flow remains light. This could create some nuisance flooding if it occurs over an urban area. Light and variable winds tonight into early Tuesday as saturation at the surface may set the stage for additional round of patchy fog across inland areas. Once the sun rises, flow will remain light and variable with the Atlantic and Gulf breezes forecast to push inland during the late morning/early afternoon hours and favor any isolated shower and storm coverage over the central interior. However, less moisture will be available (abundantly dry air aloft) for showers to form, meaning that any development would be expected to be shallow and weak in nature. Temperatures for today and tomorrow will be in the mid to upper 80s across the region, with the lower end being observed near the coastlines. Portions of the interior could approach 90 as well tomorrow. Heat indices (feels-like temperatures) may reach the middle to upper 90s each afternoon across inland communities. && .LONG TERM... (Tuesday night through next Sunday) Issued at 200 PM EDT Mon Mar 31 2025 For the latter half of the week and moving into the weekend, expansive mid-level ridging and surface high pressure over the western Atlantic will continue to strengthen and preside over the southeastern CONUS. This will most likely inhibit convection in South Florida. There will be some remaining moisture lingering in the region and the formation of the Atlantic and Gulf sea breezes. However, it will not likely be enough to overcome the increasingly dry air aloft, as well as an intrusion of drier air closer to the surface. Thus, model guidance continues to forecast very low rain chances throughout the long term period. Winds will increase by mid- week, due to the strengthening high, which will interact with low pressure over the Great Lakes region. With a tighter pressure gradient, these breezy conditions will likely to last into the end of the week and potential for gusts up to 20KT. High temperatures each day are expected in the mid 80s near the coasts and the upper 80s to lower 90s for the interior sections. With lingering moisture mid-week, there will be potential for heat indices reaching the mid-90s across the SW Florida on Wednesday and Thursday. && .AVIATION... (00Z TAFS) Issued at 758 PM EDT Mon Mar 31 2025 SHRA/TSRA through 01-02Z possible for some of the Atl terminals. Then VFR should prevail through the rest of the forecast period. Winds become light after 02-03Z, then generally SE around 10kt after 15Z. Only APF will see westerly flow with Gulf breezes developing after 16Z. && .MARINE... Issued at 1204 PM EDT Mon Mar 31 2025 Generally benign conditions to start the week through Tuesday with winds and seas gradually remaining below 10kts and 2 feet or less respectively. A few showers and storms remain possible with locally higher seas and waves in and around this activity. && .BEACHES... Issued at 1204 PM EDT Mon Mar 31 2025 A moderate risk for rip currents along the east coast continues today, but as winds continue to weaken this risk will diminish heading into Tuesday. An elevated risk is likely to return to the east coast later in the weak as onshore winds increase again. && .PRELIMINARY POINT TEMPS/POPS... Miami 72 86 74 84 / 20 10 0 0 West Kendall 69 89 71 85 / 10 10 0 0 Opa-Locka 70 89 73 84 / 20 10 0 0 Homestead 71 86 73 85 / 10 10 0 0 Fort Lauderdale 71 84 73 83 / 20 10 0 0 N Ft Lauderdale 71 85 73 83 / 30 10 0 0 Pembroke Pines 72 89 74 84 / 20 10 0 0 West Palm Beach 69 86 73 84 / 30 10 0 0 Boca Raton 70 86 73 85 / 30 10 0 0 Naples 69 85 70 88 / 0 0 0 0 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...None. AM...None. GM...None. && $$ SHORT TERM...Hadi LONG TERM....Redman UPDATE/AVIATION...17
Area Forecast Discussion
National Weather Service Morristown TN
1033 PM EDT Mon Mar 31 2025 ...New UPDATE... .UPDATE... Issued at 1032 PM EDT Mon Mar 31 2025 Forecast is progressing as expected this evening with cooling temperatures and northerly winds in the wake of a departing cold front. Clouds remain overnight, but as drier air arrives, expect gradual clearing mid- morning to mid- day on Tuesday with a mostly clear, sunny afternoon. && .SHORT TERM... (This evening through Tuesday) Issued at 212 PM EDT Mon Mar 31 2025 Key messages: 1. Cold front and associated scattered showers will move through later this afternoon and evening. 2. Dry conditions then prevail through the rest of the short term, with warmer temperatures expected tomorrow as well. Discussion: Much of the CWA is in a lull in the rain at the moment as showers and thunderstorms from last night have pushed northeast of most locations. However, high res guidance continues to indicate that an additional line of isolated to scattered showers and thunderstorms will develop along the cold front that has yet to move through. This doesn`t seem unreasonable as an upper level shortwave will swing northeast across the forecast area this afternoon, with the left exit region of a jet streak transiting the southern half of the CWA as this happens. And you can already see some weak returns forming along the front to the west of the plateau, so I think the forecast is in good shape in this regard. And I think the PoPs from largely the 12z HRRR that I used for the morning update should hold up ok as well so no additional adjustments seem necessary there. These shouldn`t be severe, but some gusty winds or even some small hail would not be out of the question. All rainfall should be east of the forecast area before midnight tonight, leaving dry conditions in place for the remainder of the short term period. Despite some post-frontal cold air advection, tomorrow should be warmer due to gradually thinning cloud cover the beginning of more substantive height rises aloft. More significant warming will be seen in the long term period. && .LONG TERM... (Tuesday night through next Monday) Issued at 212 PM EDT Mon Mar 31 2025 Key Messages: 1. Warm weather pattern for the second half of the week with temperatures 15+ degrees above normal. 2. Gusty winds for Wednesday through Thursday especially for the far east Tennessee Mountains and Foothills. 3. Frontal boundary may move across the Tennessee valley and southern Appalachians next weekend bringing another round of widespread storms. Discussion: Middle portion of the work week will be highlighted by rapidly warming temperatures and breezy conditions Wednesday into Thursday. Temperatures: Temperatures will remain mild on Tuesday with the slow clearing of the skies, but by Wednesday increasing ridging in the low levels and southerly flow near the surface will combine to drive temperatures above the 80 degree mark starting Tuesday. These conditions for warm weather will continue through the rest of the week as the incoming frontal boundary out of the midwest rams into the strong high pressure over the Atlantic/southeast US. Models continue to have the eastern Tennessee valley remain south of the front with temperatures in the upper 80`s Thursday through Saturday. Attached to the bottom of the AFD are the record high temperatures which may be in jeopardy a few days this week. Biggest question remains on the location of the stalled out boundary and how much cloud coverage it throws out, which would inhibit daytime heating. Winds: On Wednesday a strengthening low level jet will move into Middle TN and central Kentucky. This will increase southerly to southeasterly winds in the eastern Tennessee Valley and could result in a mountain wave event Wednesday into early Thursday. With the jet remaining a decent way off to our west we aren`t anticipating the extreme winds, but winds in excess of 40mph will be possible in the typically gusty locations of the southern Appalachians. Rain and Storms: Still plenty of question marks with the possibility of showers and storms for the back half of the work week and into the weekend. Like everything else with this forecast it all depends on the location of the stalled boundary to our northwest. Locations along the northern Cumberland Plateau could get several glancing blows from rounds of storms on the southern edge of the boundary and see 2+ inches of rain between Thursday and Sunday. Further south things are harder to forecast as we could see diurnally driven storms with the very warm temperatures, like we typically see in the middle of summer. These are harder to forecast until the CAMs are able to resolve this time frame, but areas north of Interstate 40/Interstate 81 have the highest chances for rainfall and most QPF. Front will finally get a shove east of the Appalachian mountains likely on Sunday which will bring widespread showers and thunderstorms before we clear out and cool down to start the upcoming work week. Daily Record High Maximum Temperatures Date Chattanooga Knoxville Tri-Cities Oak Ridge 04-02 88(2012) 88(1940) 88(2010) 87(2012) 04-03 89(1999) 85(1946) 82(2012) 87(1963) 04-04 88(1934) 87(1934) 83(2023) 84(1999) 04-05 89(2023) 89(2023) 86(2023) 88(2023) && .AVIATION... (00Z TAFS) Issued at 713 PM EDT Mon Mar 31 2025 Cold front is moving across the area with a line of showers, and a few thunderstorms, moving east of the region. This convection may impact TRI over the next hour, but it will quickly move east. MVFR cigs expected to develop overnight at TYS and TRI with 3k-3500 ft VFR cigs expected to prevail at CHA. As drier air arrives, clearing sky conditions are expected by Tuesday afternoon. && .PRELIMINARY POINT TEMPS/POPS... Chattanooga Airport, TN 42 71 54 81 / 0 0 0 10 Knoxville McGhee Tyson Airport, TN 42 68 49 81 / 10 0 0 10 Oak Ridge, TN 40 68 48 80 / 0 0 0 10 Tri Cities Airport, TN 41 65 48 76 / 30 0 0 10 && .MRX WATCHES/WARNINGS/ADVISORIES... NC...NONE. TN...NONE. VA...NONE. && $$ SHORT TERM...CD AVIATION...JB
Area Forecast Discussion
National Weather Service Omaha/Valley NE
555 PM CDT Mon Mar 31 2025 .KEY MESSAGES... - Quiet afternoon and evening today with mostly sunny to partly cloudy skies. - Showers move in late tonight into early tomorrow morning (30-40%) across our north, then gradually overspread the area during the day Tuesday. Windy conditions are expected with a Wind Advisory in effect from 11 am to 8 pm Tuesday. - PoPs increase for the late afternoon and evening hours (60-90%). A slight risk (15% chance) of severe weather exists across southern and eastern portions of the forecast area Tuesday afternoon/evening. Large hail and strong winds are the main threats. - Showers clear out by Wednesday afternoon, with low end PoPs (15-30% chance) for Thursday. More PoPs are possible Friday and Saturday (20- 40% chance). && .DISCUSSION... Issued at 341 PM CDT Mon Mar 31 2025 .SHORT TERM.../Today through Tuesday Night/ Mostly sunny to partly cloudy skies continue this afternoon as a sfc ridge of high pressure extends southward from the Manitoba area into the Dakotas and eastern Nebraska. The ridge will continue pushing eastward resulting in light winds, leading to a rather pleasant afternoon/evening. Lows tonight will be in the mid 30s north to near 40 across our south. By the late afternoon into the evening hours, we will start to see a developing sfc low across eastern Colorado induced by a deepening 500 mb trough. As the sfc low begins to deepen, it will induce a 30- 45 kt LLJ across a large swath of central Nebraska. A stream of 1000- 850 mb Gulf moisture will work in tandem with the increasing synoptic scale forcing for ascent and warm air advection to generate scattered rain showers around 6z Tuesday (30-40%), beginning across northwest portions of the forecast area. A few rumbles of thunder are not out of the question either, as some of the CAMs hint at around 100-200 J/kg across our far northern counties. Scattered rain showers will become more numerous across the forecast area during the morning hours (20-40% chance) as forcing increases with the deepening sfc low. Winds will also be on the increase, with BUFKIT soundings showing the potential to mix anywhere from 35 to 40 kts of momentum downward from the 850 mb LLJ, and also a tightening pressure gradient observed as the low deepens. Some uncertainty does exist with regards to mixing potential, given the existing clouds/rain/low level warm air advection. However, any mixing down of winds from this strong LLJ will result in windy conditions around around 30-35 mph for a large chunk of the day with gusts up to 45 mph possible. Thus, have collaborated with TOP and issued a Wind Advisory across portions of eastern Nebraska and west central/southwest Iowa until 8 pm Tuesday evening. Highs Tuesday will be slightly warmer owing to the warm air advection, with the mid 50s across the north to mid 60s across the south. Our attention then turns to the late afternoon and evening hours, as instability will be on the increase and depending on model choice, anywhere from 500-1500 J/kg of MUCAPE will stream into portions of the forecast area. How far north this axis of MUCAPE will travel will remain highly dependent on the low track and how far north the actual warm sector will make it. However, much of this instability will be elevated, with the better surface based CAPE located farther south into the Kansas area. Shear will be plentiful, with values of 50 kts or great observed, and some low level turning is also observed when looking at hodographs, so elevated supercells may develop. Along with the low track, differences in initiation of convection and its placement continue to be seen with CAM guidance. The 18z HRRR run has shown initiation a little earlier around the 19- 20z timeframe and farther west into central Nebraska, compared to the 6 and 12z runs. Other CAMs like the FV3 and RAP tend to hold off initiation until around 00z into our forecast area. Regardless of CAM choice, there does seem to be good agreement among models that storms will congeal into a line/MCS feature sometime around the 3 to 4z timeframe and then track eastward. PoP chances for Tuesday evening are anywhere from 60-90% Given the aforementioned severe potential, the Storm Prediction Center continues to highlight portions of central into eastern Nebraska and southwest Iowa in a slight risk (15% chance) of severe weather for Tuesday. The main threats with this activity continue to be large hail, and strong wind gusts as storms begin to merge into more of a linear structure. Given instability will be elevated, tornado potential is rather low despite the aforementioned low level turning. Wet bulb zero heights seem to just barely meet criteria as well, which could impact the hail potential of storms. .LONG TERM.../Wednesday through Sunday/ Showers will linger into the early morning hours Wednesday, and should exit the area by Wednesday afternoon with gradual clearing. Highs Wednesday will be in the low 50s north to low 60s across our far south. Cloud cover will be on the increase for Thursday as another mid-level shortwave materializes over the Colorado area and ejects eastward. The NBM brings in some low end PoPs across our far south late Thursday evening at around 15-30%. Southwesterly flow aloft will continue through Friday, with subtle shortwaves riding this flow, leading to continued PoP chances (20-40%) through early Saturday. Subtle model differences are observed at this time regarding placement of upper level features, however, and this may result in shifts of PoP coverage and intensity as we head into the weekend timeframe. && .AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/... Issued at 555 PM CDT Mon Mar 31 2025 VFR conditions are expected to prevail tonight into Tuesday morning with an increasing chance for MVFR ceilings developing at KOFK toward the end of the forecast period. The models continue to indicate the development of widely scattered showers late tonight into Tuesday morning with the best chance of occurrence being at KOFK. Light and variable winds will switch to southeast tonight before strengthening considerably on Tuesday when gusts of 35-37 kt are likely. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...Wind Advisory from 11 AM to 8 PM CDT Tuesday for NEZ015-018- 032>034-043>045-050>053-065>068-078-088>092. IA...Wind Advisory from 11 AM to 8 PM CDT Tuesday for IAZ043-055- 069-079-090. && $$ DISCUSSION...Castillo AVIATION...Mead
Area Forecast Discussion
National Weather Service Tallahassee FL
939 PM EDT Mon Mar 31 2025 ...New UPDATE... .UPDATE... Issued at 936 PM EDT Mon Mar 31 2025 All showers and thunderstorms have ended across the area. Still can`t completely rule out an isolated shower or two later tonight as the front sags into our area. The main concern for tonight remains the potential for fog. Nighttime microphysics satellite imagery shows a patch of low stratus and fog developing from Quincy and Tallahassee to Moody AFB. Expect more fog development through the night. Otherwise, adjusted temperatures a bit given current observations, which resulted in needing to lower lows by a degree or two. && .NEAR TERM... (Through Tuesday) Issued at 309 PM EDT Mon Mar 31 2025 The severe weather threat should be ending this evening as the squall line culprit exits to our east. Lingering showers with rumbles of thunder are possible tonight as the associated front makes its eastward push from the MS Valley. Hi-resolution models like the HRRR show convective redevelopment over Apalachee Bay into portions of the East FL Big Bend overnight, so slight-chance PoPs (20-30%) are maintained in the forecast to account. An extensive area of low stratus is then expected to blanket the region late tonight with patches to areas of fog embedded. The latter may be locally dense at times, particularly where it rained the most. The front`s nocturnal passage will lead to somewhat of a NW to SE gradient in low temperatures - ranging from upper 50s in the Wiregrass to upper mid/upper 60s along/SE of a Panama City- Tallahassee-Valdosta line. Fair weather prevails tomorrow with fog/low stratus giving way to partly cloudy skies mid to late morning. Forecast highs are in the low 80s with decent early-April sunshine. An afternoon seabreeze prompts some fair-weather cumulus spreading from the coast to the I- 10 corridor. && .SHORT TERM AND LONG TERM... (Tuesday night through Sunday) Issued at 309 PM EDT Mon Mar 31 2025 Fairly benign conditions are expected behind today`s cold front as surface high pressure and upper level ridging settles over the region. On Wednesday, southeasterly flow becomes established and persists into the weekend. This will lead to dew points in the 60s and muggy conditions prevailing. Although ridging is overhead and subsidence will prohibit storm development, with PoPs near nil, diurnal heating and the sea breeze may be able to squeeze out some fairly local shortlived showers. Otherwise, our next frontal system looks to approach the region late on Sunday into early next week. There`s some model guidance along with CPC outlooks beyond the long term that indicate a brief but sharp cool down in temperatures. Stay tuned to for additional updates as we get closer to this weekend. Expect daytime highs to increase from midweek into this weekend into the mid 80s to low 90s. Expect overnight lows in the 60s. && .AVIATION... (00Z TAFS) Issued at 729 PM EDT Mon Mar 31 2025 The showers and storms are gone with clear skies moving in from the west, which will lead to VFR conditions at all TAF sites for a few hours. After sunset, MVFR to IFR ceilings are forecast to develop and spread north across the region. Some guidance is hinting at lower visibilities, especially for KTLH and KECP, so have included some TEMPO groups for both those locations. Any low ceilings/fog should dissipate by mid-morning tomorrow with VFR conditions taking over again with a light southerly breeze. && .MARINE... Issued at 309 PM EDT Mon Mar 31 2025 A line of showers and storms is currently moving across the NE Gulf waters and is expected to be through by this evening. Winds and seas will gradually decrease through Wednesday before picking back up as southeasterly flow becomes established. && .FIRE WEATHER... Issued at 309 PM EDT Mon Mar 31 2025 The main concerns for tomorrow are fog/low stratus, followed by pockets of low dispersions in the early afternoon. Weak southerly flow is expected with an afternoon seabreeze developing. Dry weather prevails the remainder of the work week, though min RH stays healthily above critical thresholds thanks to continued southerly flow. High afternoon dispersions are forecast Wednesday and Thursday basically areawide. && .HYDROLOGY... Issued at 309 PM EDT Mon Mar 31 2025 Generally, around an inch and a half of rain is expected through the next week, there are currently no flooding concerns. && .SPOTTER INFORMATION STATEMENT... Spotter activation is not requested. However, spotters are always encouraged to safely report significant weather conditions when they occur by calling the office or tweeting us @NWSTallahassee. && .PRELIMINARY POINT TEMPS/POPS... Tallahassee 77 64 84 65 / 70 10 10 0 Panama City 74 65 79 67 / 80 10 0 0 Dothan 76 59 82 64 / 90 10 0 0 Albany 79 61 83 62 / 90 20 0 0 Valdosta 79 64 85 65 / 70 10 0 0 Cross City 78 68 83 63 / 30 10 10 0 Apalachicola 73 68 76 66 / 60 10 0 0 && .TAE WATCHES/WARNINGS/ADVISORIES... FL...High Rip Current Risk until 2 AM EDT /1 AM CDT/ Tuesday for FLZ108-112-114-115. GA...None. AL...None. GM...High Rip Current Risk until 1 AM CDT Tuesday for GMZ735. && $$ NEAR TERM...IG3 SHORT TERM...Oliver LONG TERM....Oliver AVIATION...Reese MARINE...Oliver FIRE WEATHER...IG3 HYDROLOGY...Oliver