####018007098#### FXUS61 KALY 152325 AFDALY AREA FORECAST DISCUSSION National Weather Service Albany NY 725 PM EDT Thu May 15 2025 .SYNOPSIS... Once any lingering evening showers or thunderstorms wind down, it will remain mild and muggy overnight with some patchy fog. A weak upper level disturbance and surface warm front will return the threat for some showers and thunderstorms again on Friday, with the potential for a few strong storms. Additional showers and thunderstorms are expected again on Saturday, with the potential for some strong to severe thunderstorms once again. && .NEAR TERM /THROUGH FRIDAY/... As of 725 PM EDT...Radar imagery continues to show some isolated to scattered convection, especially across the Adirondacks, Helderbergs and Hill Towns, southern Vermont and the northern Berkshires. There has been little shear in place and most of these storms have been slow moving, with storms movement depending on cell interaction and outflow. There has been some lightning from time to time, but cloud to ground strikes hasn't been overly extreme today. Due to the limited shear, these storms don't have the potential to produce strong winds, but there have been some locally heavy downpours, with a few spots across the Helderbergs, southern VT and northern Berkshires seeing over an inch of rainfall. A few small Flood Advisories have been issues for areas seeing the heaviest downpours. Outside of these areas, it has been partly to mostly cloudy with mild temperatures and muggy conditions. With sunset underway soon, convection will begin to wane with the loss of daytime heating and nocturnal effects taking over. Most showers and thunderstorms will be done by 9 to 11 PM or so. Sounding data shows plenty of llvl moisture developing under subsidence inversion, so anticipating areas of low clouds and fog, especially deeper protected valleys. Expect similar conditions overnight at KPOU as the previous night with areas of low clouds and patchy fog/br likely. Also, areas that received rainfall this aftn, have higher probability of fog/br tonight with light winds. Lows generally in the upper 50s southern Dacks to lower 60s Capital District/Hudson Valley. For Friday SPC has placed locations mainly along and south of the Mohawk Valley in marginal risk (1 out of 5) for severe storms. The pre-storm environment wl feature slightly better deep layer shear in the 20-30 knot range with sfc based CAPE values of 1500 to 2000 J/kg. In addition, better synoptic scale ascent wl arrive via 700 to 500mb s/w energy in the southwest flow aloft. This lift and instability/shear parameters supports increasing areal coverage of convection by early aftn with some stronger storms possible. Primary threat given thermodynamics would be small hail, localized gusty winds, and brief heavy downpours, especially with pw values in the 1.0 to 1.50" range. Highs wl be very similar to today with values in the upper 70s to lower 80s. Friday night is quiet with less fog/mist potential given increasing boundary layer flow of 4 to 8 knots. && .SHORT TERM /FRIDAY NIGHT THROUGH SATURDAY NIGHT/... Key Messages: - SPC has increased the marginal to slight risk (level 2 of 5) of severe thunderstorms Saturday for parts of the area. Some storms may produce damaging winds and/or large hail, along with frequent lightning and localized heavy rainfall. Discussion: Another active day is anticipated with several rounds of showers and storms likely. SPC has increased the risk to slightt (2 out of 5) for severe weather. Synoptic pattern shows approaching mid/upper lvl trof with several embedded 5h vorts rotating acrs our cwa. These strong dynamics wl interact with favorable deep layer shear of 35 to 45 knots and CAPE values of 1200 to 2000 J/kg to produce localized strong to possibly severe storms. Still some uncertainty on amount of clearing/destabilization behind morning convection, along with timing of aftn/evening energy. The pre- storm environmental conditions suggest strong shear and weak- moderate instability with good dynamics, helping increase the probability of some organized convection. In addition, localized heavy rainfall wl be possible as WPC keeps central/northern cwa in marginal risk of exceeding flash flood guidance. Highs on Saturday in the 70s to near 80F. Lows drop back into the 50s on Saturday night with lowering sfc dwpts on west/northwest winds behind boundary. && .LONG TERM /SUNDAY THROUGH THURSDAY/... Closed mid/upper lvl circulation moves directly overhead on Sunday with diurnal driven showers likely during the late morning into the aftn hours. The greatest concentration of precip/qpf wl be acrs the higher trrn of the southern Dacks/southern Greens and eastern Catskills. Highs wl be much cooler on Sunday with values in the upper 50s to mid/upper 60s. Cyclonic northwest flow and associated cold air advection continues on Monday into Tues with progged 850mb temps approaching 0C. A few lingering showers are possible acrs the favorable upslope areas of the Dacks/southern Greens on Monday with cool highs only in the 60s. Tuesday is quiet with weak high pres nosing into the area, followed by more unsettled wx for mid to late week associated with our next full latitude trof. Still some uncertainty with development and timing of system, but probability of another period of unsettled wx is increasing for mid to late week. && .AVIATION /00Z FRIDAY THROUGH TUESDAY/... Currently MVFR cigs at KPOU and KPSF, while VFR conditions prevail at KALB and KGFL this aftn with light and variable winds. Expect cigs to slowly improve to VFR conditions at all sites in the next 1 to 3 hours with a few isolated to widely scattered showers and embedded rumbles of thunder. Have utilized PROB30 groups this aftn/evening to cover this potential as winds remain light under 8 knots. Tonight CIGS lower to MVFR with greatest potential for IFR/LIFR cigs at KPSF and KPOU between 06-12z Friday. Vis will be mostly VFR but MVFR/IFR vis possible at KPSF/KPOU in a mix of mist and fog. Conditions trend toward MVFR between 12-15z and all sites should have VFR conditions by 15z Friday as south winds increase 5 to 10 knots. Outlook... Friday Night: Moderate Operational Impact. Chance of SHRA...TSRA. Saturday: High Operational Impact. Definite SHRA...TSRA. Saturday Night: Moderate Operational Impact. Chance of SHRA. Sunday: Moderate Operational Impact. Breezy. Chance of SHRA. Sunday Night: Low Operational Impact. Breezy. NO SIG WX. Monday: Low Operational Impact. Breezy. NO SIG WX. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. MA...None. VT...None. && $$ SYNOPSIS...Frugis NEAR TERM...Frugis/WFO BTV SHORT TERM...WFO BTV LONG TERM...WFO BTV AVIATION...WFO BTV ####018006087#### FXUS65 KVEF 152325 AFDVEF Area Forecast Discussion National Weather Service Las Vegas NV 425 PM PDT Thu May 15 2025 .SYNOPSIS...Temperatures will continue to warm through Friday before another potent weather system drops into the region over the weekend, bringing strong gusty winds, a chance of precipitation, and a drop in temperatures. Calmer and warmer weather is expected next week. && .SHORT TERM...Tonight through Sunday. Low impact weather is expected through Friday. Weak height rises are expected tonight which will keep winds calm and skies clear. On Friday, a weak shortwave embedded in the mean flow will shift through the region. This feature will be dry in the low levels but have some mid to upper level moisture associated with, there will be increasing clouds from northwest to southeast through the day, but no rain is expected. An uptick in winds is possible as this piece of energy moves through, but gusts should remain under 20 MPH in most locations with gusts up to 25 MPH possible in the Mojave Desert wind- prone areas. High temperatures on Friday will be a few degrees warmer than today, which will be near normal for this time of the year. A stronger, more impactful trough will dig into the region this weekend, which will bring potentially impactful winds and precipitation chances. The main concern will be winds as widespread gusty southwest winds will set up on Saturday as the pressure gradient increases with the deepening system. A strengthening jet also sets up across the Western Mojave Desert through southern Nevada into Arizona. Probabilities for over 40 MPH gusts are over 50% through this region, and many ensemble members show 40-50MPH gusts on Saturday. Decided to issue a Wind Advisory for these areas as confidence is high enough for wind impacts on Saturday. May need to add some locations if confidence increases for gusty winds and wind impacts, especially in Death Valley and the Sierra into the Owens Valley, but did not have enough confidence that widespread wind impacts will occur at this time in those areas. A few ensemble members around Barstow, CA as well as Desert Rock, NV show 55 MPH+ wind gusts on Saturday, but do not have enough confidence for a High Wind Watch/Warning now. Later shifts can now focus on adjusting headlines and wind impact levels as we enter the hi-res model domain and changes in probabilities lead to higher confidence. Southwest winds will slowly diminish Saturday evening, with gusty wind and wind impacts lingering the longest through the Western Mojave Desert. On Sunday, winds will turn northwest as the trough axis moves through. The best chance for wind impacts with gusts over 40 MPH on Sunday will be in Esmeralda, central Nye, and northern parts of Inyo County as the front washes out as it moves further south. Additional wind headlines may be needed on Sunday in parts of the Southern Great Basin or the Owens Valley, but held off as confidence was lower and it was uncertain how widespread the north wind impacts would be on Sunday. The best chance for precipitation will be through southern Nevada and northern Mohave County where showers and thunderstorms may develop Saturday and Sunday. This is where PWATs will increase to 125 to 175 percent of normal (generally between 0.50 and 0.75 inches), which will allow for moderate-to-heavy rain rates beneath any thunderstorms that develop, but generally light rainfall is elsewhere. At this time, it looks like the greatest threat of thunderstorms will be across central Nye and northern Lincoln counties Saturday and across central Nye and the remainder of Lincoln County Sunday. Further west, the forecast is trending drier as moisture will be scoured out too quickly behind the trough axis. Other than some light precipitation on the Sierra Crest, most of the California zones should remain dry. Temperatures Saturday and Sunday will cool slightly each day as the system moves inland. .LONG TERM...Monday through Wednesday. Behind the trough, ridging sets up for the start of the work week that will result in Las Vegas chances for 90 degrees rapidly increasing through the week and "Moderate" HeatRisk (Level 2 on a scale from 0 to 4) returning to the low valleys. && .AVIATION...For Harry Reid...For the 00Z Forecast Package...Light and variable winds late this afternoon will become predominantly out of the southwest by early evening and remain less than 10 knots through the night. A brief period of light northeast winds is expected tomorrow morning before shifting to the southwest and becoming gusty after 18Z. Once the turn to the southwest occurs tomorrow, expect winds to remain from that direction through Saturday. VFR conditions will prevail through tomorrow night with bases remaining AOA 15kft AGL. For the rest of southern Nevada, northwest Arizona and southeast California...For the 00Z Forecast Package...The Las Vegas area TAF sites will see conditions similar to those described above for Harry Reid. Elsewhere, except KDAG, area TAF sites will see light winds of less than 10 knots into tomorrow morning. KDAG will see the typical gusty westerly winds develop after 02Z this evening. By tomorrow afternoon, all regional terminals will see winds increasing out of the south to southwest, with 20 to 25 knots gusts becoming common by late afternoon. VFR conditions will prevail through tomorrow night with bases remaining AOA 15kft AGL. && .SPOTTER INFORMATION STATEMENT...Spotters are encouraged to report any significant weather or impacts according to standard operating procedures. && $$ SHORT TERM...Nickerson LONG TERM...Soulat AVIATION...Planz For more forecast information...see us on our webpage: https://weather.gov/lasvegas or follow us on Facebook and Twitter ####018007818#### FXUS63 KGLD 152326 AFDGLD Area Forecast Discussion National Weather Service Goodland KS 526 PM MDT Thu May 15 2025 .KEY MESSAGES... - Overall drier Thursday but a 10-15% chance for severe downbursts associated with virga/sprinkles/showers are possible Thursday afternoon mainly west of Highway 25. - Breezy winds are forecast to continue through the weekend and into the start of next week. - A more active pattern then sets up this weekend and into the start of the week with daily chances for storms Saturday through Monday. Severe weather may be possible each day with the current favored day being Sunday. && .SHORT TERM /THROUGH FRIDAY NIGHT/... Issued at 126 PM MDT Thu May 15 2025 A large low pressure system is currently spinning across South Dakota attributing to a breezy wind field continuing for the forecast area through the day with wind gusts around 40 mph. Not anticipating any blowing dust concerns today but some very localized reductions in visibilities near fields may be possible as we did receive an MPing report of some dust near a field in northern Sherman county during the morning hours, have not had any details of what the visibility was. As the low continues to spin some vorticity maxima along with additional support with a 500mb shortwave increases the mid level moisture some. Am continuing to think that some virga, sprinkles or spotty showers are possible with this forcing, however with dry low levels in wake of yesterday's front do think any form precipitation will be hard pressed to reach the surface. I do still have some concerns of severe downburst potential in the dissipating stages of any updraft as Corfidi downshear vectors remain around 60 knots and inverted v soundings in place. HREF max wind gusts also do support this potential as well as hinting at some splotchy instances of 50-55 mph winds primarily along and west of Highway 25 into the evening hours; given how strong the Corfidi downshear vectors are and the winds at the top of the inverted v soundings do think there is some potential for sporadic wind gusts of 55-65 mph. Friday, the low pressure system across the northern Plains begins to move to the east and as it does so wind across the norther portion of the forecast area increases in response to this, would not be surprised if we have some 45 to even 50 mph winds across SW Nebraska. May need have an increase in fire spread potential especially if those winds do pan out as RH values are then forecast to fall into the upper teens to low 20s as the majority of out SW Nebraska counties missed out on any rainfall. Saturday, troughing across the western CONUS begins to take shape and moisture begins to return to the area from the southeast. Winds do look to become breezy with the southeastern winds as well gusting to 35-40 mph during the afternoon hours. High temperatures in the mid 70s to low 80s are currently forecast. The majority of the day does look to be dry but during the afternoon a mid level shortwave does look to move into the northwest portions of the area. Dew points are fairly meager in the 40s based on current model guidance but wind shear is more than adequate around 40 knots to support some potential organization of storms. Large hail at this time looks to be the primary hazard. An even more conditional threat may be further south as moisture will be a little bit better along the northern extent of the moisture advection. The forcing further south is not nearly as good but does need watching. && .LONG TERM /SATURDAY THROUGH THURSDAY/... Issued at 126 PM MDT Thu May 15 2025 For the extended period, Sunday is currently the day to watch. A deep trough continues to move towards the area as a surface low begins to develop across southern Colorado and is forecast to eject northward across the CWA. Moisture is forecast to continue to stream into the area ahead of these features. Fog and stratus may be present as well during the morning hours Sunday with the continued stream of moisture advection. As the low moves to the north additional mid level forcing associated with the incoming trough ejects into the area. As the surface low begins to eject this will create a dry line to the east and a warm front moving to the north. All of these features combined sets up for a classic severe weather event for portions of the area. Forecast soundings show 1500-2500 j/kg and near 50 knots of effective shear in place across the area. Forecast soundings do show a cap in place through the afternoon so that may hinder development some but 12Z NAM runs indicate loaded gun soundings in place. As of current model guidance the difference between this set up and the other more conditional cap issue days is that the area has additional and closer to the area forcing that should help overcome this. Everything mentioned above all aligns with the current Day 4 15% outlook that the Storm Prediction Center has over the majority of the CWA. Will continue to monitor trends but at this time all hazards may be in play during the afternoon and evening hours for the CWA. Monday, the trough continues to move across the area and the surface low does some retrograding across Nebraska which may again brings some concern for some thunderstorm potential, severe potential for the CWA is a little iffy at this time based on the quality of moisture across the area. Winds do remain breezy as well throughout the day again gusting around 30-40 mph during the afternoon. Another breezy day is in store Tuesday as this low finally departs the area, on the back side of the system the GFS is currently indicating a 700mb jet of 45-55 knot wind gusts if this trend continues then winds may need to be increased a bit in future forecasts. Wednesday and through the remainder of the extended period, am seeing an increased signal for ridging developing across the western CONUS. If this continues then a reprieve from active and maybe even breezy conditions and a warm up may ensue. && .AVIATION /00Z TAFS THROUGH 00Z FRIDAY/... Issued at 514 PM MDT Thu May 15 2025 VFR conditions and northwesterly winds are expected to prevail for both KGLD and KMCK through the period. For KGLD, sporadic gusts up around 20 kts are still expected until about 0130-0200Z, after that winds will generally be sustained under 10 kts, but gusts up around 15 kts are possible all night. KMCK is going to see more consistent gusts until the nocturnal inversion sets up, around 0200-0230Z, and then the gusts will weaken to around 15 kts, too. There is a chance at LLWS overnight at both KGLD and KMCK, but it looks to be spread over the the bottom 500-700 feet for about 40 kts. Some weak convective showers are in the region and may briefly impact either of the TAF sites, but no IFR conditions are expected. Most likely impact would be some rain and erratic winds. Confidence for convection noticeably impacting KGLD or KMCK is less than 10%. Tomorrow morning, winds will kick up again as the inversion disappears. Gusts in the morning will quickly jump up to around 20-28 kts. 18Z through the rest of the period, KGLD is expected to see 30 kts gusts while KMCK should expect 30-40 kts gusts. As the sunsets tomorrow and the inversion returns, winds will rapidly weaken. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...None. CO...None. NE...None. && $$ SHORT TERM...Trigg LONG TERM...Trigg AVIATION...CA ####018006426#### FXUS62 KCHS 152328 AFDCHS Area Forecast Discussion National Weather Service Charleston SC 728 PM EDT Thu May 15 2025 .SYNOPSIS... Broad high pressure will remain across the area into the weekend. A weak cold front could approach the region this weekend with high pressure prevailing thereafter. A much stronger && .NEAR TERM /UNTIL 6 AM FRIDAY MORNING/... Early this evening: Overall, a very quiet and early summer-like overnight period is expected. Coming off an afternoon with highs in the low 90s and with persistent southwest flow driven by a nearby inland trough, it will be a very mild night. Lows are forecast to only dip into the upper 60s for inland areas while the coastal corridor lingers in the low 70s. && .SHORT TERM /6 AM FRIDAY MORNING THROUGH SUNDAY/... Friday: The hottest day of the year so far seems likely across the region as strong upper ridging holds across the Southeast States. H8 temperatures are forecast to rise to 17-19C with low- level thicknesses peaking 1420-1425 m during peak heating. This coupled with little in the way of significant cloud cover and a downslope flow aloft should allow highs to reach into the lower-mid 90s just above everywhere except along the immediate coast where a late afternoon resultant sea breeze will take shape. Record highs at both the Charleston and Savannah Intl Airports could be challenged. The record in Downtown Charleston/Waterfront Park looks safe for now given where the resultant sea breeze is expected to set up, but even a slight delay in its development will have implications for Downtown Charleston. Modified forecast soundings show the atmosphere remaining strongly capped through the day with no forcing aloft noted given the orientation of the upper ridge. A rain-free forecast was maintained. Dewpoints are now forecast to mix out a bit more than previously expected with value dropping into the upper 60s/lower 70s. The resulting heat indices peak in the 98-101 range and well below the 108 Heat Advisory criteria. While this is a tad lower than previous forecasts, the baseline key message remains that extra precautions should be taken given its the first significant heat episode of the year. Note, the experimental Heat Risk level is solidly in the orange/risk level 2 category all but the beaches. It will be a warm overnight with lows dropping into the upper 60s/lower 70s, except mid 70s at the beaches and Downtown Charleston. Saturday: The upper ridge aloft will steadily weaken with the flow aloft becoming more zonal with time. A cold front will meander into South Carolina and Georgia during the day, but there is much uncertainty how far south the front will drift as it becomes increasingly parallel to the flow aloft. Some degree of convection will accompany the front as it moves into northern Georgia, the Upstate into western North Carolina Saturday morning, but guidance remains mixed on how much activity will take it this far south into southern South Carolina into Southeast Georgia during the late afternoon into the evening hours given the mean westerly flow ahead of the front. A number of the GEFS members are showing measurable rainfall over the area as the front settles south, but the 15/12z operational GFS still looks to have some convective feedback issues. For now, the 15/13z NBM is favored, but with slightly wetter guidance blended in to trend. This still yields gridded pops just below 20%, but these are certainly higher than the previous forecast cycle. Mentionable pops may eventually be needed if models trend wetter overall. It will remain hot and somewhat humid with highs warming into the lower-mid 90s away from the immediate coast. Lows will drop into the upper 60s/lower 70s with mid 70s at the beaches and Downtown Charleston. Sunday: The frontal remnants will linger nearby through the day as a sea breeze moves inland. There may be enough instability and convergence ahead of the sea breeze to generate a few showers/tstms, mainly inland from the coastal corridor. Slight chance pops were maintained. Highs will warm into the upper 80s/lower 90s away from the beaches. && .LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/... Upper ridging will mostly dominate aloft through Tuesday before the a large upper trough will impact the eastern CONUS by the middle part of next week, helping to push a stronger cold front across the Southeast States. The front will bring the next meaningful chance for showers and tstms. Temperatures will remain above average through Tuesday, then return closer to climatology Wednesday into Thursday. && .AVIATION /00Z FRIDAY THROUGH TUESDAY/... VFR conditions will prevail at KCHS, KJZI, and KSAV through 00z Saturday. Extended Aviation Outlook: The risk for showers/tstms will increase by the middle of next week. && .MARINE... Tonight: Sea breeze surges in the Charleston Harbor should end shortly after sunset. Otherwise, southwest winds 10-15 kt will prevail overnight for all waters with seas 2-4 ft. Friday through Tuesday: Southerly wind regime will prevail for much of the period. Another sea breeze surge looks like Friday along the land/sea interface and Charleston Harbor. Winds increase a bit more all areas for Saturday ahead of an approaching cold front. Winds may reach as high as 15-20 kt during this time. Otherwise, speeds will remain less than 15 kt, except higher near the sea breeze. Seas will generally remain 4 ft or less through the period. && .CLIMATE... Record High Temperatures: May 16: KCHS: 94/1941 KSAV: 95/1915 May 19: KSAV: 97/1996 May 20: KSAV: 96/2006 Record High Minimum Temperatures: May 16: KCHS: 71/2018 KSAV: 74/1915 May 17: KCHS: 74/1995 KCXM: 75/1998 KSAV: 74/1995 May 18: KCHS: 75/1995 KCXM: 77/1991 KSAV: 74/1899 May 19: KSAV: 74/1930 May 20: KCHS: 72/2022 KCXM: 76/2022 KSAV: 73/1896 May 21: KCHS: 74/2022 KSAV: 74/2017 && .CHS WATCHES/WARNINGS/ADVISORIES... GA...None. SC...None. MARINE...None. && $$ NEAR TERM...BSH SHORT TERM... LONG TERM... AVIATION...BSH MARINE...