Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 05/04/22

National Weather Service Albany NY
945 PM EDT Tue May 3 2022 .SYNOPSIS... Dry weather this evening will give way to a steady rainfall for tonight. Some additional showers are expected through the day tomorrow, along with cool and cloudy conditions. Milder temperatures, along with a partly to mostly sunny sky, will return for Thursday, as high pressure builds into the region. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... UPDATE...As of 930 PM EDT, some light showers/sprinkles were located across the southern Adirondacks/upper Hudson Valley and portions of southern VT. As isentropic lift increases on the 300-310 K surfaces, expect additional bands of light showers to overspread areas near and especially north of I-90 through 11 PM. Farther south, a few showers/sprinkles will develop south of I-90 toward and especially after midnight across the eastern Catskills, southern portions of the Capital Region and northern Taconics/Berkshires. As a strengthening low level jet approaches from the southwest, and with a pocket of low/mid level dry air above the boundary layer, some gusty southeast winds will persist over the next 1-2 hours, until steadier rain saturates these layers closer to or just after midnight. Some gusts of 25-30 mph may occur within some north/south oriented valleys, including around the immediate Capital Region, as well as some higher elevations of the eastern Catskills, SW Adirondacks, and on the south side of the Mohawk Valley. Previous discussion follows... As of 334 PM EDT...Surface high pressure is currently offshore eastern New England is departing off to the east. The flow around this high pressure area has been allowing for a moist east to southeast flow in the area, allowing for plenty of clouds around. Although weak ridging has been in place aloft, the ridge axis will be shifting to the east this evening, as a fast moving storm system starts approaching the area from the Great Lakes and Ohio Valley. Although there had been some breaks in the clouds this afternoon, mid and high level clouds are already increasing from the west and skies will become mostly cloudy to overcast for the evening. Although the evening will start off dry, isentropic lift will lead to rain moving in for the overnight hours. 3 km HRRR suggests some spotty light rain or showers could start impacting the Adirondacks and Mohawk Valley as early as 8 or 9 PM, although the bulk of the precip will be arriving after midnight, as a large shield of rain moves west to east across the area for the late night hours. Most of the rain will be light, although some brief moderate bursts can`t be ruled out, especially for the Adirondacks. The best forcing looks to be across northern areas, so rainfall amounts will likely be lighter for far southern areas and heaviest across the Adirondacks, where the low-level jet will locally enhanced precip for the southern facing slopes. Instability looks fairly limited, but can`t totally rule out a rumble of thunder for southern or southwestern areas towards daybreak as Showalter values approach zero. Overnight lows will generally be in the mid to upper 40s. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH THURSDAY NIGHT/... On Wednesday, the best isentropic lift will shift northeast of the area during the morning hours. However, the threat for additional showers will continue through the entire day as low pressure passes across the area and the upper level shortwave crosses the region. Model guidance seems to suggest that while all areas will see some light rain through the day, the steadiest and heaviest amounts will likely be located across the northern half of the area. Still can`t totally rule out a stray rumble of thunder for southern areas, although the best chance of elevated instability will likely be south of the forecast area. With the widespread clouds and precip, as well as the moist southeast flow, temps will be held down into the 50s for the entire day. As the storm departs, it will remain damp and cool into Wednesday night with precip ending. As some breaks in the clouds occur, patchy fog will form, although this will depend on how light winds remain and if any drier air starts working its way into the region. Temps will fall into the 40s, although some upper 30s are possible in the Adirondacks. High pressure will build into the area for Thursday into Thursday night. This will allow for dry weather and skies will become partly to mostly clear. With a recent amount of sun expected on Thursday, temps should rise well into the 60s with afternoon dewpoints falling into the 30s. Despite the decent mixing, winds won`t be too strong for Thursday and should remain under 15 mph. Dry weather will continue into Thursday night with lows in the mid 30s to mid 40s, and frost is expected for areas where the growing season has begun. && .LONG TERM /FRIDAY THROUGH TUESDAY/... Main uncertainty during the long term revolves around track of closed mid/upper level low, which most guidance suggests will track from the Ohio Valley region toward the mid Atlantic coast between Friday and Sunday, with upper level ridging then building across the region from the north/west early next week. Given confluent upper level flow across the northeast states and southeast Canada for Friday-Sunday, there will likely be a sharp northern edge to associated steady precipitation and thicker cloud cover associated with system tracking to our south. Consensus of guidance (NBM) generally brings slight chance PoPs as far north as around I-90 Saturday afternoon, with chance PoPs farther south, before PoPs slowly drop off from north to south Saturday night into Sunday. So, chances for light rain basically for SE Catskills, mid Hudson Valley and NW CT late Friday into Saturday, before potentially shifting back southward during Sunday. However, there remains uncertainty regarding this northern edge, so ultimately additional changes to forecast will remain possible. Best chances for dry weather and less clouds this weekend will be across southern Adirondacks into southern VT. By early next week, model consensus suggests upper level ridging and a surface high build southward, keeping the region dry along with a gradual moderating temperature trend. As for temps, daytime highs Fri-Sun will be dependent on where thicker clouds and precipitation occur; with highs mainly in the 50s (if not for some upper 40s) possible for southern areas, and mid 50s to lower/mid 60s for northern areas. Overnight lows mainly in the 30s and 40s, with some lower 30s or colder mins possible (esp Sun AM) across portions of the southern Adirondacks, southern VT and the Lake George/Saratoga region, assuming skies remain mostly clear. For Mon/Tue, high temps should warm into the 60s and 70s (especially valley areas by Tuesday), assuming aforementioned ridging builds into the area. Lows again in the 30s and 40s, coldest across the southern Adirondacks and southern VT. Could be some large diurnal temperature changes given a potentially dry air mass in place. && .AVIATION /02Z WEDNESDAY THROUGH SUNDAY/... Low pressure will track into western New York State overnight, then redevelop near Long Island during Wednesday before tracking northeast off the New England coast Wednesday night. Patchy light rain will develop this evening at KGFL and possibly KALB, between 00Z-02Z/Wed. Despite the light rain, conditions should generally remain VFR during this time. Steadier rain will then overspread the TAF sites from west to east between 05Z-08Z/Wed, with Cigs dropping to MVFR, and Vsbys ranging from VFR to MVFR. A few periods of moderate rain will be possible shortly after daybreak Wednesday, possibly producing periods of IFR Vsbys/Cigs, especially through around 18Z/Wed. The rain may become more showery, and/or taper to drizzle Wednesday afternoon. However, still expect widespread MVFR Cigs/Vsbys to linger through most of Wednesday afternoon, with a few periods of IFR possible, especially for Cigs. The best chance for a longer period of IFR/LIFR conditions will be KPSF Wednesday afternoon. Southeast winds will increase to 8-12 KT this evening, with a few gusts of 20-25 KT possible at KALB and KPSF through around 05Z/Wed. Winds may decrease slightly toward 12Z/Wed to 5-10 KT. During Wednesday, southeast winds at 4-8 KT will become light/variable around midday, then trend into the north to northwest during the afternoon at 5-10 KT. Outlook... Wednesday Night: Low Operational Impact. Slight Chance of SHRA. Thursday: No Operational Impact. NO SIG WX. Thursday Night: No Operational Impact. NO SIG WX. Friday: No Operational Impact. Slight Chance of SHRA. Friday Night: Low Operational Impact. NO SIG WX. Saturday: Low Operational Impact. Slight Chance of RA. Saturday Night: Low Operational Impact. NO SIG WX. Sunday: No Operational Impact. NO SIG WX. && .FIRE WEATHER... A wetting rainfall is expected across the entire area for tonight into Wednesday. RH values will remain above 70 percent through the day on Wednesday and into Wednesday night. Southerly winds of 5 to 10 mph tonight and Wednesday will become north to northwest by Wednesday night around 5 mph. Dry weather will return on Thursday with afternoon RH values back down to around 30 percent. Northwest winds will be 5 to 10 mph on Thursday. && .HYDROLOGY... No hydrologic problems are anticipated through the rest of the week. Forecast rainfall through the next 7 days is an inch or less. As a storm system impacts the region, 0.25 to 0.75 inches of rain is expected tonight into tomorrow, which will allow for some small rises on rivers and streams. Any rises look very fairly minor and no flooding is anticipated. Drier weather returns Thursday. Another area of low pressure may bring some showers to southern areas Friday into Saturday, but rainfall amounts generally look to be on the lighter side. As a result, rivers and streams will mainly be holding steady for the late week and into the weekend. For details on specific area rivers and lakes, including observed and forecast river stages and lake elevations, please visit the Advanced Hydrologic Prediction Service /AHPS/ graphs on our website. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. MA...None. VT...None. && $$ SYNOPSIS...Frugis NEAR TERM...Frugis/KL SHORT TERM...Frugis LONG TERM...KL AVIATION...Evbuoma/KL FIRE WEATHER...Frugis HYDROLOGY...Frugis
Area Forecast Discussion
National Weather Service Bismarck ND
1013 PM CDT Tue May 3 2022 .UPDATE... Issued at 1013 PM CDT Tue May 3 2022 An area of light rain showers that is seemingly tied to weak upper level divergence is located over eastern Montana. Radar trends show some of this activity could move into northwest North Dakota overnight. RAP 700-600 mb RH seems to have a good handle on the location of the showers, which was relied upon to add a slight chance of rain to the forecast. Only trace amounts of rain are likely. UPDATE Issued at 638 PM CDT Tue May 3 2022 No major changes are needed for this update. A few high-resolution models depict a narrow corridor of fog west of Jamestown early tomorrow morning, so a patchy fog mention was added to the forecast. && .SHORT TERM...(This evening through Wednesday) Issued at 345 PM CDT Tue May 3 2022 Warmer and dry conditions through this week with highs in the upper 60s and possible the lower 70s in the end of the week. Breezy winds this afternoon in the southwest as the pressure gradient tightens between the surface low in Wyoming and the high pressure to our northeast. These winds should relax after sunset. A shortwave ridge will continue this afternoon and through tonight before split flow takes over with ridging to our north and a low moving through Nebraska. No precipitation for us with this low. Temperatures overnight will be in the mid to upper 30s with increasing clouds. High temperatures Wednesday will warm up to the upper 50s in the south to upper 60s in the west and north. .LONG TERM...(Wednesday night through Tuesday) Issued at 345 PM CDT Tue May 3 2022 Finally, temperatures will be at or above average through the week. Then a chance of thunderstorms this weekend and early next week. Temperatures could reach into the 70s late week. Split flow will continue until Thursday night when southwest flow takes over on the leading edge of a broad trough. Multiple low pressure systems could move through embedded in this trough. The cluster analysis shows uncertainty in the amplitude and timing of this incoming trough. The NBM temperature spreads also reflect this with a large spread in the high temperatures through the period. Our next chance of rain will be Saturday afternoon with a cold front extending down from a low pressure system in southern Canada. Thunderstorms are possible Saturday with this through the evening. QPF looks to be under an inch. The greatest probabilities for 0.25 or more ending 12z Sunday are over the eastern half of the forecast area at 50 percent. Probabilities drop to less than 30 percent in the same area for 0.50 inches or greater through the same timeframe. Sunday morning a low pressure from the Northern Rockies moves in, bringing another chance of rain Sunday. A slight ridge then forms Sunday night before the next system that could impact the area with more rain Monday through Tuesday. 48 hour QPF ending Tuesday morning for this early next week system looks to be around 0.50 inches. The probability of 0.25 or greater is 50 percent in the northwest and 70 percent in the southeast. Probabilities then drop to 30 percent across the forecast area for 1 inch or greater for the same timeframe. Uncertainties are high of course being this far out. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday evening) Issued at 1013 PM CDT Tue May 3 2022 Some patchy fog could develop near KJMS early Wednesday morning. Otherwise, VFR conditions are expected through the forecast period, with south to southeasterly winds around 10 kts. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...Hollan SHORT TERM...Smith LONG TERM...Smith AVIATION...Hollan
National Weather Service Hastings NE
700 PM CDT Tue May 3 2022 .DISCUSSION...(This evening through Tuesday) Issued at 452 PM CDT Tue May 3 2022 -- Highlights/primary concerns of the entire 7-day forecast in chronological order: 1) A wet and seasonably-cool Wed-Thurs on tap: Our 1-day "dry break" today (still so odd to type this given recent extreme dryness) comes to an end already tomorrow into Thursday as a slow-moving low pressure system brings us a couple of more seasonably-cool and dreary days punctuated by off-and-on rounds of showers and isolated-to-scattered NON-severe thunderstorms. Unlike our last system that was pretty much a 12-15 hour washout as it moved through progressively, this one will move considerably slower and keep rain chances (zero concern for "sneaky snow" this time!) around on-and-off for a solid 36-48 hours. Measurable rain will certainly not occur this entire time, but even during the drier periods pockets of pesky drizzle could easily kick in. Although forecast 2-day cumulative rain totals (still straight-up WPC QPF at this point) will surely undergo further adjustments, we are currently calling for most of the coverage area (CWA) to tally between 0.50-1.50" (generally lowest north/west and highest south/east. While most areas will obviously not have fully dried before rain returns, we are fairly confident that most areas are under little-to-no threat for organized flooding given the fairly modest expected totals and the fact that the soil can likely still handle a fair amount of rain (evidenced in part by the lack of significant rises on area stream/river gauges despite a widespread 2-4" over the past week). 2) A chance to dry out, warm up and hopefully see at least a halfway-decent dose of sunshine Friday-Saturday daytime: Friday should finally break what will end up being a 4-day stretch of solidly-cooler-than-average conditions for early May, with a return to highs well into the 60s-low 70s, with even warmer 70s to around 80 expected Saturday (which along with a return to breezy south-southeast winds Saturday should help things dry out again). 3) Our next window of opportunity for at least one (maybe two) chances for strong-to-severe storms returns Saturday evening into Sunday (along with a few comments on current SPC outlooks): Although still a few days too soon to attempt much detail, both the ECMWF/GFS suggest that a round of strong to perhaps severe storms could develop near/just northwest of our CWA late Saturday afternoon-early evening before moving into our area, with perhaps another round of strong to severe convection trying to fire Sunday afternoon as a front heads back north. Not surprisingly, model support for this possible first round is at least a bit higher at this point than for the second round. As for the SPC severe outlooks that were issued early this AM, we fully note that they opted to highlight parts of our CWA for a possible severe risk on Days 6-7 (Sunday-Monday). However, based on the latest model data (yes, still very subject to change) if anything we are a bit more concerned here about Saturday evening-Sunday, with Monday currently looking considerably more questionable for any severe threat given that latest models mainly depict a warm and breezy day with most convection holding north. -- With the most important points covered, will dive into a bit more day-to-day detail to wrap things up: - Current/recent weather situation as of 4pm: Although dry as expected, today proved to be a bit tricky in the cloud cover/temperature department. In short, low stratus clouds held firmer than some models suggested (especially in our eastern half), and even while stratus broke up in west-southwest areas a veil of higher clouds moved in from the west. The net result has been mainly mostly cloudy to cloudy skies today, which along with the fairly light winds/limited mixing today (speeds generally only 5-15 MPH initially from the north this morning and now east this afternoon) has held temperatures modestly below expectations from the initial overnight forecast package. More specifically, most areas now only look to top out low 50s at best (instead of mid- upper 50s). In the mid-upper levels, water vapor imagery and short term model data clearly depict our next weather-maker in the form of a closed low slowly churning toward us from the UT/WY/CO border area. At the surface, the aforementioned light winds today result from the presence of a roughly 1018 millibar high centered over eastern NE. - This evening-overnight: Of highest confidence is that the vast majority of the CWA will remain dry the vast majority of the night, with only a handful of far western counties assigned any "official" small PoPs very late in the night (closer to sunrise). However, the main uncertainties involve cloud trends and resultant hour-to-hour temperature trends (a continuation of today`s uncertainty). While confidence is fairly high that a widespread, low stratus deck will redevelop and/or fill in again at some point tonight, the unusually- optimistic NAM suggests this will not occur until very late, while the HRRR/RAP (which have overall had a better handle this afternoon) suggest a pretty rapid redevelopment of low clouds already by shortly after sunset. While these differences could easily have some effect on how quickly especially pre-midnight temps rise or fall, fortunately the development of light-but- steady 5-15 MPH east-southeast breezes overnight "should" keep things from really "tanking"...even IF the first part of the night is clearer than expected. As a result, have lows aimed low 40s most areas, and even the upper 30s forecast in far northern/west central zones remaining at least barely above "frost potential territory" (something to watch closely though). Once low clouds do establish, think at least patchy drizzle will be possible almost anywhere (especially closer to sunrise) and have added this to the forecast along with the aforementioned small chances for actual rain showers in western areas. Lastly, while not expected to be a major issue, did add some generic "patchy fog" again to far western zones a few hours either side of sunrise, as hinted at by various models including HRRR (although widespread clouds could hinder much fog development). - Wednesday daytime-night: While rain chances return, want to emphasize again that this will not be a total "washout" (as Monday largely was). In fact, the majority of scattered showers/weak storm potential in the morning will likely remain largely in our western half before chances eventually spread farther east into the CWA during the afternoon and especially evening-overnight. However, even where steadier showers/storms are not occurring, pesky light drizzle could easily develop or persist, so finding TRULY dry conditions could be tough to come by. Over the course of these 24hrs, the heart of the main upper low will track from CO into western KS, while a surface low will track eastward well to our south (into the Southern Plains). Thus, we will clearly be on the cool side of this system with only minimal elevated instability and essentially no severe storm risk. However, various rounds/pockets of showers/weak storms are likely through this time. At the surface, steady 10-20 MPH east-southeast breezes will prevail through the day, then turn more northerly overnight as the surface low passes to our south. Temp-wise, feeling increasingly-confident that we may again fall short of forecast highs given widespread clouds/areas of precip, and although maybe not enough, did already lower 3-4 degrees from previous forecast, now calling for only low-mid 50s at best. - Thurs daytime-night: This is "part 2" of our 36-48 hour rain chances, as the center of the aforementioned upper low tracks from western KS (sunrise Thurs) to MO (by sunrise Friday). As it passes by, more chances for off-and-on showers/weak storms will accompany it. Although would not be surprised to see high temps lowered in later forecasts, maintained mid-upper 50s for now. It looks to be a somewhat breezy day too, with generally north winds gusting at least 20-25 MPH. Although a few slower model solutions suggest that the last bit of light rain/drizzle may still be lingering near our eastern edges at sunrise Friday, our official forecast again goes dry by that time. - Friday daytime-Saturday daytime: Already covered much of this in "number 2" above, but other than maybe some pesky light rain/drizzle right away Fri AM in our east, this looks to be a rather high-confidence dry 36 hours, as broad/fairly flat upper riding prevails in between disturbances. Breezes Fri appear rather light, but then south-southeast winds pick up a bit Saturday daytime. As a result, high temps Saturday are aimed a good 5-8 degrees warmer than Friday, and easily the warmest day of the month so far. - Saturday night-Sunday night: Already touched on thunderstorm/possible severe weather concerns in "number 3" above. While plenty of uncertainty remains, at least the latest ECMWF/GFS are in decent agreement that Saturday evening-night is probably our most "evident" strong-to-severe storm risk at this point as a low amplitude wave approaching in west-southwest flow aloft teams with a weak surface boundary arriving in northern NE during the afternoon. Although low level moisture/instability levels look to be a possible limiting factor (dewpoints currently progged mainly mid 50s), especially the GFS generates around 1500 J/kg CAPE and fairly decent deep layer shear of 40-50KT. Sunday is certainly the bigger question mark regarding whether another round of strong-severe convection is possible (?). High temps Sunday actually nudged down 3-5 degrees from previous (low 70s north to upper 70s south). - Monday-Tuesday: No point in much detail at this time range, but if anything compared to 24hrs ago, models appear more insistent in developing a blocking pattern. This effectively keeps the next large-scale western trough from aggressively entering our region, but instead holds it out west (due to eastern CONUS ridging) and gives us varying "glancing blows" of lift along its eastern periphery. This raises a lot of question marks about convective potential, which if anything seem to be trending lower. For what it`s worth for being a week out, the latest ECMWF/GFS are in surprisingly-decent agreement on the large scale scene, suggesting a mainly warm/dry/breezy day Monday (widespread 80s for highs) and then at least a slightly cooler day Tues (current forecast mainly mid 70s- low 80s). && .AVIATION...(For the 00Z KGRI/KEAR TAFS through 00Z Thursday) Issued at 700 PM CDT Tue May 3 2022 MVFR conditions persist at KGRI and KEAR terminals this evening as ceilings remain an issue. Clouds are expected to thicken up this evening and into the overnight hours, with low stratus moving in once again after midnight. MVFR/IFR will be possible after 10Z at KEAR and KGRI. Periodic showers will be possible in the vicinity of the terminals through the day, with better chances for widespread activity coming in the late afternoon/evening. Winds through the forecast period remain east-southeast around 6-11kts. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ DISCUSSION...Pfannkuch AVIATION...Wekesser
Area Forecast Discussion
National Weather Service North Platte NE
708 PM CDT Tue May 3 2022 .SHORT TERM...(This evening through Wednesday night) Issued at 358 PM CDT Tue May 3 2022 An upper trough and closed low will move into Wyoming and western Colorado tonight. Moisture will be drawn in ahead of this system across western Nebraska. Chance to likely POPS will develop across the western half of the forecast area after midnight and eastward across the remainder of the area on Wednesday. In addition to the showers, patchy fog is also show by the latest HRRR and RAP to develop late tonight across the west and spread into the central Sandhills Wednesday morning. There will also be MUCAPEs up to 300-400 j/kg across southwest and central NE to support a chance for a few embedded thunderstorms Wednesday afternoon and evening. Highs Wednesday will be cool from the upper 40s to lower 50s. The upper low is forecast to move into western Kansas late Wednesday night, with likely POPs forecast across the southwestern half of the area. QPFs through Wednesday night look to be fairly light from a tenth to a quarter inch most locations. .LONG TERM...(Thursday through Tuesday) Issued at 358 PM CDT Tue May 3 2022 The upper low will move slowly east from western into central Kansas on Thursday with likely POPs to continue across the southeastern half of the area. The 12Z ECMWF is slightly further north with this low center indicating to potential for higher QPFs across much of western and north central Nebraska. Highs Thursday to remain on the cool side ranging in the 50s. The system will move southeast of the area Thursday night, with weak upper ridging and dry conditions for Friday. A broad upper trough will deepen across the western U.S. Saturday through Tuesday. Impulses ejecting from this longwave trough will bring a chance for showers each day, with thunderstorms also possible during the afternoon and evening hours. Southwesterly flow aloft will increase. The area is expected to remain in the "warm sector" during much of this timeframe. This is shown more substantially by the 12Z ECMWF than the 12Z GFS. Highs forecast to range mostly in the 60s and 70s through the period. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday evening) Issued at 707 PM CDT Tue May 3 2022 Low clouds will move into the area later this evening. Expect widespread MVFR ceilings at the KVTN terminal and IFR ceilings at the KLBF terminal after 06z Wednesday. Light rain showers are expected to begin Wednesday morning and will persist into the afternoon hours. Winds will be from the east or east southeast at around 10 to 15 KTS through 00z Thursday. && .LBF WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...Roberg LONG TERM...Roberg AVIATION...Buttler
...Updated Aviation Forecast Discussion...

.DISCUSSION... Issued at 322 PM CDT Tue May 3 2022 Mostly cloudy and cool across the region this afternoon as the surface low that brought our widespread precip into early this morning was spinning over IL. Aloft, a ridge axis was sliding across NE and was helping to dissipate some of the clouds across western and central NE. Still, temperatures were in the mid 40s to mid 50s across the area...around 15 to 25 degrees below average for this time of year. Meanwhile, water vapor imagery revealed a cutoff low over northern UT that is progged to slide east-southeast through KS and MO in a similar fashion to yesterday`s system, bringing more widespread showers and perhaps a few storms to the area Wednesday into Thursday night and possibly Friday morning. Current consensus would place the heaviest precip (1-2") across southeast NE into far southwest IA with lesser amounts toward 1/4" to 1/2" in northeast Nebraska. Should also note that prior to that system arriving, there are some signs we could get some drizzle or a few showers Wednesday morning, with RAP soundings suggesting 1+ km of saturation in the low levels and some isentropic lift/weak warm air advection in the area. If this occurs, we could have some visibility reductions during the morning commute, but plenty of other guidance says it`s unlikely, so not including anything in the forecast at this time...just something to keep an eye on tonight. Once the precip exits Friday, expect a brief period of upper level ridging to lead to some drying time. However, southerly return flow will begin ushering in warmer, moist air for the weekend into early next week while a large scale upper level trough sets up over the western CONUS. The general idea is that we`ll see a few rounds of showers and storms into early next week as various bits of shortwave energy/boundaries move in/near the area, but still quite a bit of spread in guidance on exact timing and placement. Given the strengthening upper level flow and instability progged to be in the area, will likely see at least one round of severe weather from the Saturday evening through Tuesday timeframe, but again, timing and placement remains in question. For what it`s worth, greatest ensemble/deterministic agreement is on storms forming over central/western NE Saturday afternoon/evening and then pushing into the forecast area during the evening/overnight hours. Beyond that, there is a lot of spread, and each day`s shower and storm chances will likely be impacted by what happens the previous night. Bottom line, it`s looking like we`ll see a somewhat active pattern this weekend into early next week with some potential for severe weather. Temperature-wise, we`ll be staying cool through the remainder of the week, with highs generally in the 50s, and 60s by Friday. By Saturday we`ll be warming up with the aforementioned southerly return flow. Expect highs in the 70s in most areas this weekend with widespread highs in the 80s looking likely early next week, pending any precip timing of course. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday evening) Issued at 630 PM CDT Tue May 3 2022 Low VFR ceilings 3K-4K AGL are common across the forecast area early this evening. Expect trend to continue through the first six hours of the TAF period as low level ridge axis will be oriented across western Iowa and eastern Nebraska. After midnight, low level east to southeast isentropic flow and ascent allowing MVFR ceilings to advect into TAF sites between 07-10 UTC. As the morning level progresses, isentropic ascent expected to increase in response to approaching upper level system. Diabatic processes or small scale impulse appear to enhance isentropic ascent enough for the development of light drizzle, as noted by CAMS and point soundings. Better rain chance expected late in the TAF period with the approach of stronger upper level system. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...None. IA...None. && $$ DISCUSSION...CA AVIATION...Fortin
Area Forecast Discussion
National Weather Service Blacksburg VA
833 PM EDT Tue May 3 2022 .SYNOPSIS... A frontal boundary will oscillate north and south of the region over the next several days. This will result in several rounds of showers and thunderstorms throughout the week. By the weekend, an anomalous upper low will settle southward along the Mid- Atlantic coast bringing a period of damp and unseasonably cool temperatures to the area. && .NEAR TERM /THROUGH WEDNESDAY/... As of 820 PM EDT Tuesday... Adjusted probability of precipitation this afternoon and evening. Satellite and surface analysis showed the warm front stalled over Buckingham county this evening. The next cluster/broken line of thunderstorms was continuing to develop from around Lewisburg to northwest North Carolina. The environment ahead of this activity was still unstable enough to maintain storms overnight but they are not expected to be as intense as the storms that went through Tuesday afternoon. Hi-Res guidance including the HRRR have these showers and thunderstorms progressing across southwest Virginia and northern North Carolina overnight. No changes to temperatures needed at this time. A cold front will reach the Virginia/West Virginia line late tonight, then push east across our region on Wednesday with scattered thunderstorms especially in the foothills and piedmont of Virginia and North Carolina. && .SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY NIGHT/... As of 210 PM EDT Tuesday... Brief Period of Dry Conditions, Followed by Another System Arriving by Friday Morning A bit of upper level ridging builds in following the frontal passage for a brief period of high pressure and dry conditions for Wednesday night through Thursday. A warm front enters the area from the SW, bringing rain and thunderstorm chances to the North Carolina High Country and Southern Blue Ridge early Friday morning. There are some differences in models regarding how early precipitation arrives on Friday, but will likely be in the area by mid-morning. Instability looks to remain limited in the morning, but increases throughout the day as temperatures warm. Temperatures are expected to reach the mid 70s west of the Blue Ridge and upper 70s in the east on Thursday, but cool to the low to mid 70s on Friday. Forecast confidence is moderate. && .LONG TERM /SATURDAY THROUGH TUESDAY/... As of 205 PM EDT Tuesday... Lingering Rain for the Weekend, Drying for the Beginning of Next Work Week... The surface low and associated cold front moves to the east, toward the NC Atlantic Coast by Saturday morning. Shower and thunderstorm chances linger across the area behind the front as another surface low develops in the Ohio Valley. This system will move offshore by Sunday, with surface high pressure following behind for Monday and Tuesday, and a return to drier conditions. Northwest flow behind the system will keep temperatures on the cool side for the beginning of the work week. Forecast confidence is moderate. && .AVIATION /00Z WEDNESDAY THROUGH SUNDAY/... As of 830 PM EDT Tuesday... Satellite and surface analysis showed the warm front stalled over Buckingham county this evening. The next cluster/broken line of MVFR thunderstorms was continuing to develop from around Lewisburg to northwest North Carolina. The environment ahead of this activity was still unstable enough to maintain storms overnight but they are not expected to be as intense as the storms that went through Tuesday afternoon. Hi-Res guidance including the HRRR have these showers and thunderstorms progressing across southwest Virginia and northern North Carolina overnight. MVFR clouds will develop overnight. MVFR fog is also possible where it rained Tuesday afternoon and evening. A cold front approaches Wednesday morning. Winds will be from the southwest tonight ahead of the front then turn to the west behind the front Wednesday. As mixing begins in the morning gusts of 15 to 25 kts will develop. A few showers and isolated thunderstorms with MVFR ceilings and visibility are expected in the foothills and piedmont of Virginia and North Carolina ahead of the cold front, especially after 18Z/2PM. Average confidence on wind, visibility and ceiling. Above average confidence on probability of thunderstorms. Extended Aviation Discussion... Wednesday night and Thursday expect VFR conditions with no rain expected and clearing skies. By Friday, a deep upper low will bring several rounds of showers and thunderstorms with the associated MVFR conditions through Sunday. This will also increase the probability for late night and early morning IFR/LIFR fog. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...None. NC...None. WV...None. && $$ SYNOPSIS...KK/SH NEAR TERM...AMS/KK SHORT TERM...AS LONG TERM...AS AVIATION...AMS/KK
Area Forecast Discussion
National Weather Service Topeka KS
547 PM CDT Tue May 3 2022 ...AVIATION UPDATE... .DISCUSSION... Issued at 238 PM CDT Tue May 3 2022 Key messages: 1. Rain chances increase Wednesday afternoon through the day on Thursday. A few inches possible. 2. Can`t rule out a severe storm or two into Thursday afternoon. 3. Much warmer temperatures into early next week - possibly close to 90 degrees, already! Currently, the forecast area over northeastern and east central KS is in a transition zone with a low pressure system departing to the east with associated frontal boundaries situated well southeast of the area and an approaching upper level Pacific system steadily encroaching into the central Rockies at this hour. Wrap around moisture and cooler air has been able to maintain low stratus over the region with limited mixing and only weak dry air advection over portions of the area. This evening, stratus will be tough to break for long at all with the incoming beginning to return winds and moist advection from the southeast into the this evening and over night as a weak ridge aloft passes overhead. Into the day tomorrow, an area of low pressure develops on the lee of the Rockies with a digging trough aloft. This will begin to encourage moisture flux into the region and as the baroclinic zones sharpen, isentropic ascent will increase over the region helping to develop a widespread precipitation shield over the area. Anticipating that PWs increase to around the 75th percentile range so a healthy amount of rain should be seen across the majority of the area through the day on Thursday as the system lifts generally to the east/northeast across the area. All told, right now, have settled on 1.5 to 2 inches of QPF across the area. Depending on localized amounts, some areas could see close to 3 inches and right now that looks to be over north central into northeastern areas that would love to see the moisture. Let`s hope the track of the system continues as is for now to realize those amounts. If ensemble data hold true, then these amounts should be common. Into the afternoon on Thursday, also can`t rule out a period of severe weather potential across east central portions of the area. Some models are more robust with advection and overall stronger with the upper system so height falls and lapse rates in the mid levels are stronger. Should this come to fruition, then I can`t rule out an elevated storm that could go severe with mostly a hail risk for a few hours. An interesting twist that may need to be watched is that of a weak low level inversion layer with more warming near the surface due to WAA than anticipated. Wind fields look interesting and thus hodographs for this period, especially with regard to the GFS. This could allow for surface based storms which may bring about a short period of increased potential where a tornado may not be able to be completely ruled out. This potential is so low right now that is not being messaged other than an idea at this point. As the storm system exits the area, ridging sets up for the weekend with a drying trend in place. Should be ideal conditions with temperatures in the 70s. A warm up with continued southerly flow sets up into Monday with highs pushing into the 80s and dare I say 90 at this point. Uncertain on storm potential at this point into this period. && .AVIATION...(For the 00Z TAFS through 00Z Thursday) Issued at 547 PM CDT Tue May 3 2022 Unfortunately it looks like the MVFR CIGS are going to remain over the terminals for some time in part due to the lack of mixing within the weak surface ridge. The RAP and NAM show CIGS lowering towards the end of the forecast period as SHRA move in from the southwest so IFR CIGS seem plausible. Mid level lapse rates appear to be supportive of elevated TS as well. && .TOP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ DISCUSSION...Drake AVIATION...Wolters