Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 04/23/25


Area Forecast Discussion
National Weather Service Bismarck ND
1014 PM CDT Tue Apr 22 2025 .KEY MESSAGES... - Near to slightly below normal temperatures through the work week are forecast to be followed by warming trend through the weekend. - After a mostly dry Wednesday, low to medium chances for rain return to southern North Dakota on Thursday. - Medium to high chances for rain showers statewide Saturday through next Tuesday, with low chances for thunderstorms Sunday through Monday. && .UPDATE... Issued at 1010 PM CDT Tue Apr 22 2025 Surface low pressure has shifted into southeast Manitoba as of 1000 PM CDT, with an upstream closed upper low analyzed near the ND/SK/MB border intersection. The scattered shower activity across central North Dakota has nearly concluded. Meanwhile, light rain and snow continue to fall across northern parts of the state, mainly north of Highway 2. Recent webcam imagery indicates some relatively heavier snow showers across Divide and Burke Counties, with visibility impacted. This snow is not being detected by radar and is absent from most forecast guidance, except for the RAP which suggests snow gradually dissipating in the northwest overnight, but perhaps shifting farther east towards the Turtle Mountains. UPDATE Issued at 656 PM CDT Tue Apr 22 2025 Scattered shower activity has become more prevalent along a corridor from near Sidney, MT to Bismarck. This trend will likely persist until closer to sunset. Farther north, precipitation has mostly been limited to areas along the Canadian border for the past couple hours. Snow had been mixing in with rain as recently as late afternoon, but as of 630 PM CDT it appears that all precipitation is falling as rain or drizzle. There is still potential for some light snow to return to the Turtle Mountains later tonight, with little to no accumulation expected. Model guidance also suggests very low ceilings with drizzle/mist/fog in the Turtle Mountains area persisting through the night and perhaps lasting as long as early Wednesday afternoon. Have added a mention of patchy fog to the forecast to account for this. May need to monitor for potential freezing drizzle in the Turtle Mountains later tonight should precipitation remain as liquid, but guidance shows uncertainty in this outcome. && .DISCUSSION... Issued at 300 PM CDT Tue Apr 22 2025 Currently a surface low pressure in northeast North Dakota is slowly moving east. Precipitation wrapping around the low is present in southern Canada and northern North Dakota. In eastern Montana scattered showers have formed in the cyclonic flow. These are moving into northwestern North Dakota, but being diurnally driven, they will die around sunset. A pressure gradient and high pressure bubble is the reason for the windy west winds today. Thursday a surface high pressure will move in from the west, creating much calmer winds. Aloft, a quick moving shortwave ridge will move with it. Highs will only be in the 50s as cooler air is with this high. Friday southwest flow develops over the Rockies and Northern Plains, starting our daily chances of rain through early next week. Temperatures could warm into the lower 70s across the west and south by Sunday as warmer air moves through the southwest flow. Sunday night a low pressure could form off the Rockies in Colorado, and move into South Dakota (potentially) on Monday. Models are already suggesting some level of thunderstorms off the warm front. The NBM has 25 percent chance of thunder Monday. The rain will start Sunday night on the outer edge of the low and continue through Monday evening. For QPF the GEFS plumes are all over the place for accumulations, mainly for this weekend. They seem to agree that for the daily accumulations will likely be 0.20 or less generally across the area. For this weekend`s potential low the 6 hour hourly QPF is around 0.20 but we are several days out. If it turns out to be thunderstorms Monday, there will be higher QPF of course. && .AVIATION /00Z TAFS THROUGH 00Z THURSDAY/... Issued at 1010 PM CDT Tue Apr 22 2025 MVFR ceilings are expected to prevail across northern North Dakota through tonight, with conditions improving from west to east during the day Wednesday. Some areas along the Canadian border could see IFR/LIFR ceilings through the night, along with light rain/snow and drizzle/fog. For the southern half of western and central North Dakota, VFR conditions are expected to prevail. Winds will mainly be northwest around 5 to 15 kts through Wednesday. && .BIS WATCHES/WARNINGS/ADVISORIES... None. && $$ UPDATE...Hollan DISCUSSION...Smith AVIATION...Hollan
Area Forecast Discussion
National Weather Service Billings MT
708 PM MDT Tue Apr 22 2025 .KEY MESSAGES... - Scattered showers/mountain snow Wednesday evening, increasing Thursday. - Temperatures increase through the week peaking near 70 Saturday. - Another storm system taking shape for the weekend into early next week with possible impacts. Stay tuned. && .UPDATE... Satellite imagery shows a confluent WNW flow over the region, which is associated with a ~1020mb Canadian surface high which is still a bit to our north. W-NW winds have decreased quite a bit over the past 1-2 hours (as we approach sunset) and this will translate to light N-E winds per the aforementioned surface high. There is an upstream wave over OR/ID showing hints of baroclinicity per cooling cloud tops from OR/ID to south central MT. As our low level winds turn easterly/upslope, scattered rain/snow showers will impact our southwest mountains and foothills thru the night. A couple inches of snow should fall over the Beartooth-Absarokas, and Red Lodge may even see a dusting of snow tonight. As forcing slowly increases, light rain/snow showers may spread to lower elevations like Billings and Hardin by daybreak Wednesday. Finally, the backdooring wind shift will bring increased low level moisture into our northeast zones, and HRRR is starting to pick up some fog from Miles City to Baker starting around 09z. This seems reasonable given upstream dewpts in the lower 30s and expected lows around 27-30F. Have added patchy fog to this area from 09-15z. JKL && .DISCUSSION... Through Thursday night... Winds will be breezy out of the north/northwest this afternoon as steep low level lapse rates and 20-25 kt 850 mb winds mix down to the surface. Snow showers may persist (30%) over the mountains while rain showers will be possible (15%) across the lower elevations. The next chance for widespread precipitation will be Wednesday evening into Thursday as a 500 mb wave moves across the region. Low pressure to our south and high pressure to our north will combine to advect moisture into the region with easterly winds. The lack of instability and straight line hodographs will limit thunderstorm development. The NBM is giving locations southeast of a line from Livingston to Miles City a 30-50% chance of getting greater than 0.25 inches of precipitation. The most favorable areas for precipitation will be locations in the mountains and foothills due to favorable upslope. Snow levels will be around 6,000 ft with north and east facing slopes in the Beartooth mountains having a 40 to 60% chance for getting greater than 4 inches of snow and the Bighorn mountains having a 20 to 30% chance. High temperatures will be in the 50s F Wednesday before decreasing slightly into the 40s F for Thursday. Most of the short term will feature partly to mostly cloudy skies. Torgerson Friday through Tuesday... Forecast area will be under diffluent flow ahead of the next Pacific trough on Friday. Clusters already differed in the strength of this trough at this time. Model trough differences continued on Saturday with Clusters suggesting some sort of split to the trough as it`s still on the W coast. Diffluent flow continues over the forecast area. Trough shifts E toward the region on Sunday with Clusters continuing to vary in their depictions of the trough. The trough moves over the region on Monday with uncertainty continuing in the strength and position of the system. The trough continues to shift E on Tuesday. Given the above, there will be low to moderate precipitation chances Friday through Saturday night, then precipitation chances will be high Sunday into Monday night, before decreasing on Tuesday. Gulf moisture will be tapped Friday into Sunday. PWAT`s will be on the order of 0.50-0.75 inches Friday into Monday per the SREF and NAEFS. PWAT anomalies will be on the order of 200% of normal Sunday into Monday, which means a lot of precipitation is possible for the forecast area. Ensembles showed a very large spread in possible precipitation amounts for Monday through Tuesday. NBM probabilities of 0.50 inches QPF for 48 hrs from 12Z Sun-12Z Tue is 50-60% with 20-50% chances for an inch. There were low to medium chances for 6 inches of snow in the mountains above 6000` for this period, and minimal chances for any foothills snow. Current total forecast liquid precipitation amounts from Sunday through Tuesday were near an inch over most of the area, with higher amounts from KBIL S and SW. With elevated snow levels, rain on snow is a concern over the foothills and the high precip. amounts will be a concern for the burn scars including the Elk Fire. There will be possible thunderstorms Friday based on the SREF which showed a 30% chance of surface CAPE over 500 J/kg and Bulk Effective Shear at 30 kt or greater in the WSW part of area. Added thunder to these areas. Clusters indicated that CAPE/shear could support thunderstorms over the weekend, especially in the E. Had isolated thunderstorms across the area. Expect gusty SE winds over the SE on Friday. Monday has the potential to be a windy day with gusty NW winds based on ECMWF ensemble wind gusts and a strong pressure gradient behind departing low pressure. The weekend will be warm, with normal temps expected for the remainder of the period. Stay tuned to the forecast for changes. Arthur && .AVIATION... VFR conditions will prevail through the period. Isolated rain/snow showers are possible in the mountains. Expect obscurations with showers. Patchy fog is possible tonight into Wednesday morning, from KMLS to the Dakota borders. Matos && .PRELIMINARY POINT TEMP/POPS... Wed Thu Fri Sat Sun Mon Tue ----------------------------------------------------------- BIL 035/054 040/049 039/060 041/071 046/068 046/056 042/059 12/W 37/W 52/W 23/T 46/T 78/W 54/W LVM 032/051 036/048 036/054 039/067 041/061 041/052 036/057 12/W 37/W 53/T 23/T 37/T 78/W 44/W HDN 033/056 040/051 038/062 041/072 044/070 045/058 040/059 13/W 57/W 62/W 33/T 46/T 78/W 64/W MLS 030/054 038/051 036/057 044/073 046/073 048/059 041/059 11/E 35/W 43/W 22/T 34/T 67/W 54/W 4BQ 034/056 040/047 039/054 045/074 049/073 048/059 040/056 12/W 57/W 52/W 22/T 24/T 57/T 54/W BHK 027/053 033/053 031/056 041/070 045/072 045/062 037/058 11/B 25/W 43/W 23/T 34/T 66/T 54/W SHR 030/056 035/047 035/058 039/071 041/068 041/056 036/056 13/W 68/W 52/W 32/T 24/T 68/W 65/W && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...None. WY...None. && $$ weather.gov/billings
Area Forecast Discussion
National Weather Service Cheyenne WY
542 PM MDT Tue Apr 22 2025 .KEY MESSAGES... - Moist southeasterly flow alongside a stalled frontal boundary between WY/CO will produce a thunderstorm risk on Wednesday with a marginal risk of severe activity. - Adequate low and mid level moisture along with passing weather disturbances will help produce scattered afternoon and evening showers and thunderstorms nearly every day. && .SHORT TERM /THROUGH WEDNESDAY NIGHT/... Issued at 122 PM MDT Tue Apr 22 2025 Satellite shows some clouds developing along the Interstate 80 corridor this afternoon where weak lift and instability is also present. Hi-Res guidance shows a weak convergence boundary at the surface, roughly along a line from Cheyenne to Scottsbluff. This convergence zone will be the likely area where showers develop and then push eastward. Given the dry surface, its possible showers will not develop at all in the CWA this afternoon. However, radar already shows weak returns just across the border in Colorado. Any showers that do develop will likely not have much moisture. Dry, inverted-V soundings suggest high cloud bases, so rain will likely evaporate before reaching the ground. Inverted-V soundings also point to these being gusty showers, with DCAPE values east of the Laramie Range around 600 J/kg. Not expecting anything severe at this time, but would not be surprised to see a rogue gust to 50 MPH under these showers. Shower activity could will die off after sunset. Tricky forecast headed into Wednesday as synoptic models show different solutions from Hi-Res guidance. An incoming upper-level shortwave will try to push a weak cold front into the CWA tomorrow. Concurrently, a stationary front will exist across eastern Colorado which will likely spark convection across this area. Synoptic models are in fairly good agreement that the stationary front will keep the cold front at bay along the northern border of the CWA, allowing decent instability and steep lapse rates to develop. Model soundings from the GFS show about 1000 J/kg of MUCAPE in the southern Nebraska panhandle with effective shear values greater than 30 kts. Hi-Res guidance like the HRRR and RAP seem to think the cold front will move across the area tomorrow, stabilizing the atmosphere. Both models show very little instability Wednesday afternoon with no storms developing. Other Hi-Res guidance like the NAMNest does show a bit more instability leading to run of the mill thunderstorms during the afternoon and evening. Other CAMs seem to be more aggressive, vaguely showing our typical Chugwater supercell developing during the afternoon and tracking across the Nebraska panhandle during the evening hours. SPC has issued a Marginal Risk for severe weather Wednesday, mainly for areas south of Alliance and Wheatland, but east of the Laramie Range. Given this information, if storms do develop tomorrow, they will likely be at least marginally severe with good low-level moisture advection. The chance for both large hail and strong winds will be possible, depending on which model solution pans out. Regardless of which solution comes to fruition, convection will likely die off by midnight, per most model guidance. && .LONG TERM /THURSDAY THROUGH TUESDAY/... Issued at 122 PM MDT Tue Apr 22 2025 Mid-level water vapor shows an active Pacific Ocean resulting in an active long term with almost daily precipitation chances starting Thursday. A low pressure system pushing in from the Pacific northwest will send a negatively trough through the Intermountain West. Models are in pretty good consensus with CAPE values between 1000 to 2000 j/kg. There also looks to be a stream of vorticity with a couple vorticity maxima`s that may lead to some discrete cell development in the afternoon and some stratiform rain with some possible embedded weak thunderstorms in the evening due to the warm air advection as well. The Intermountain west will be in a southerly flow to help bring in moisture from the Gulf and saturate the mid to lower levels allowing for precipitation to reach the ground. Most of the models have the storms/showers either move off or die off by 06z as a weak transient ridge sets up over us to give us a slight break before another wave sets up for another round of convection Friday afternoon. This wet pattern looks to continue through the beginning of the next work week. Mid level temperatures look to remain positive remaining in warmer temperatures in the 50/60`s through Friday and 60/70`s for this weekend. The other added benefit will be the overnight temperatures remaining in the 30/40`s over the next 7 days. && .AVIATION /00Z TAFS THROUGH 00Z THURSDAY/... Issued at 542 PM MDT Tue Apr 22 2025 Plentiful mid/upper level cloudiness this evening will partially clear tonight, keeping VFR conditions for eastern Wyo and western Neb terminals. Wind will be the main aviation weather concern through the night as gusty west winds transition to northeast and eventually east. Ceilings lower tomorrow afternoon as additional moisture streams into the area. Nebraska terminals will approach MVFR as showers and thunderstorms develop, primarily after 23/21z. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...None. NE...None. && $$ SHORT TERM...SF LONG TERM...MM AVIATION...DS
Area Forecast Discussion
National Weather Service Hastings NE
650 PM CDT Tue Apr 22 2025 .KEY MESSAGES... - Continued dry and pleasant for most of the area this evening and overnight. - Rain chances increase for Wednesday, particularly for the afternoon into overnight hours, and includes the risk for marginally severe storms. - Periodic shower and thunderstorm chances continue nearly every day through the end of the forecast period, though confidence on coverage, timing, and placement remains low. The "driest" period looks to be late Thursday night through Friday evening. - Early indications are that are more organized system and potential for severe weather will come on Monday. && .DISCUSSION... Issued at 440 PM CDT Tue Apr 22 2025 All in all, as advertised, today has been a very pleasant day with plentiful sunshine, temperatures in the 70s, and steady, but modest, easterly breeze. I don`t really see this changing through the evening hours. Main change to the forecast in the short term was to back off on shwr/tstm chcs late tonight and into Wed AM. Suspect most, if not all, of the thunderstorm development this evening along a stalled boundary (currently from around DDC to HYS to CNK) will remain just S/SE of the forecast area. Could perhaps see some expansion overnight further N with a developing LLJ, but even recent HRRR runs have really backed off on this for all but perhaps our KS counties. As such, have limited anything more than slgt chc PoPs through 15Z to along and S of the KS/NE state line. Suspect most of the area will remain dry through Wed AM, with perhaps the biggest uncertainty being how far N the primary frontal zone drifts, and how much low cloud cover accompanies it. Model consensus is for the front to be draped SW to NE somewhere over the middle of the CWA, which could present the opportunity for a solid 15 deg temp from from Ord to Beloit. Current high temp grid is not this dramatic, but could easily temps trending cooler in the far N, and warmer in the far S once uncertainties on stratus potential become clearer. This same boundary should serve as a focus for new (iso-scat?) tstm development at some point during the aftn-early eve hrs. Both CAPE and shear appear to remain modest, but probably sufficient for a marginally severe storm, or two...esp early on in the convective cycle when convection is more isolated and able to take advantage of steeper low level lapse rates. Given the proximity to the boundary, can`t completely rule out an iso tornado, or maybe even landspout given stalled nature of the boundary and marginal deep layer shear...but feel the threat is too iso/minimal to message more broadly at this point. At least S portions of the area will retain a scat shwr/storm potential through the overnight and into Thu AM, though probably not on the severe side. Worth noting that the 18Z HRRR hinted at the potential for a summer-like MCS over KS and even a wake low further N sometime late Wed night into early Thu AM. Sensible weather on Thursday is a pretty big question mark as it will likely depend on coverage, timing, and placement of convection from the previous 12-18 hrs. Gut feeling is that we`ll see at least one (maybe two) semi-organized rounds of shwrs/tstms work through the area on Thu into Thu night, but doubt much if any of this will be too intense given likely weak instability. Again, how much, where, and when still highly uncertain. As is often the case with convection around here, amounts will likely be highly variable with "winners" getting as much as 0.5-1.5", whereas the "losers" get little to nothing. IF severe convection were to become a concern, think it would be mainly along/S of the state line. Still appears a decent shortwave trough and accompanying cold front will sweep through the area Thu night or Fri AM and clear most of the area of moisture/organized precip for the day & eve Fri. Between the copious clouds/rain on Thu and the cooler N breeze behind the cold front on Fri, should expect cooler highs mainly in the 60s each aftn. Risk of frost/freeze appears low, even for our NW. Return flow will establish itself once again Fri night into Sat as a large high system shifts E/SE through the Great Lakes region. Models hint at some elevated activity encroaching on our far W zones as early as Sat AM, but think the vast majority of the day and the CWA will remain dry most of Saturday with temps in the 60s to low 70s (depending on cloud cover). Could see a repeat of elevated shwrs/storms over parts of the area Sat night into Sun AM, but at least the EC keeps this spotty then capped to deep convection the rest of the day. Have a feeling the going forecast for the weekend is going to wind up sounding much worse/wetter than what we`ll have in reality. The next decent chc for organized precip should come on Mon with the arrival of a moderately strong shortwave/upper jet streak and attendant sfc low pressure system. Details still murky, of course, at this time range (including timing)...but general pattern suggests an increased potential for organized severe weather over the Plains region, and we already included in the 15% Day 7 outlook. Certainly envision some scenarios where higher probs are eventually introduced over or near the forecast area, once the details become clearer. This is definitely our most "synoptically evident" severe weather potential over the next week. Ensembles suggest the high pressure that moves in behind this system could clear out moisture well S of here and keep us dry for several days mid to late next week. Temperatures should be fairly seasonable or even slightly above normal. && .AVIATION /00Z TAFS THROUGH 00Z THURSDAY/... Issued at 648 PM CDT Tue Apr 22 2025 For KGRI/KEAR Airports: Low confidence CIG and shower/storm forecast this period. Tonight: Quiet conditions and light E-NE winds should prevail through midnight. Later tonight, some short term model guidance is much more aggressive than other`s in developing elevated convection and/or low CIGs (at least MVFR). However, other guidance suggests any convection will be isolated and favor areas further S/SE of the terminals...and models that typically over-predict low stratus this time of year are mainly clear. Therefore, have kept any lower clouds as SCT and held off until closer to dawn for this inclusion. We continue to monitor model trends and make next shift aware of the wide spread in guidance. Confidence: Low. Wednesday: Forecast uncertainty carries into Wednesday, as well...esp in the AM. Models range anywhere from socked in low stratus (MVFR or even IFR) and perhaps some scattered elevated convection to mainly clear and dry. Seems reasonable that convection would be more probable for the aftn as a boundary edges northward and diurnal instability increases. Thus, have held off any PROB30 groups for shwrs/storms until the aftn hrs. Because of the uncertainty, maintained VFR conditions, for now. Winds look to be E to NE 6-11kt, with some modest gusts 15-20kt. Confidence: Low. && .GID WATCHES/WARNINGS/ADVISORIES... NE...None. KS...None. && $$ DISCUSSION...Thies AVIATION...Thies
Area Forecast Discussion
National Weather Service Houston/Galveston TX
621 PM CDT Tue Apr 22 2025 ...New AVIATION... .SHORT TERM... (This evening through Wednesday Night) Issued at 233 PM CDT Tue Apr 22 2025 Showers have begun to move inland from the Gulf this afternoon, tapping into the moisture provided by southwesterly flow aloft and onshore flow at the surface. With CAPE around 2000 J/kg and vorticity maximums passing overhead, may see some storms fire up alongside these showers as the afternoon progresses. While storms are not projected to be as strong as what was observed yesterday, as the previous forecaster mentioned it is the time of year when SE TX routinely has favorable dynamics for some storms to go rogue and become stronger in nature. Shear values aren`t all that impressive (20-35 kt range) and with the vorticity maximums not all that...well...maximum...not expecting to see anything wildly strong or severe. Mostly expect that if any did approach the stronger end of a typical thunderstorm it would likely produce a decent amount of rain (thank you 90th percentile PWATs) and isolated stronger gusts of wind. Also mentioned by the previous forecaster was the potential for an MCS early Wednesday morning. 12Z HRRR continues to hold onto this idea of an MCS tracking across the state and making it into SE Texas around sunrise on Wednesday. The complexity lies in that it is the only Hi-Res model that has been consistent with this possibility...all other Hi-Res models have shown the MCS fizzling out well before it reaches SE Texas. Have opted to lean more towards the HRRR since it is *usually* better at handling convective systems. In any case, not expecting anything severe to occur with this system. It could produce some gusty winds as it rolls through, and it certainly has the potential to drop around 0.25"-1.0" of rain (potentially isolated higher amounts in the stronger parts of the system). Temperatures for tonight and tomorrow night will be pretty similar with lows in the upper 60s to low 70s. Highs for Wednesday will be in the low 80s inland and in the upper 70s to around 80 degrees along the coast. && .LONG TERM... (Thursday through next Monday) Issued at 233 PM CDT Tue Apr 22 2025 We continue our slow march towards summer weather through the weekend and into the beginning of next week, which will be characterized by chances for scattered storms and gradually warming temperatures that will approach the 90 degree-mark. The overall pattern will remain relatively unchanged for both Thursday and Friday, with global models indicating a persistent onshore surface flow regime while a series embedded shortwaves traverse a quasi-zonal flow in the midlevels. This should be sufficient to trigger the development of scattered thunderstorms on both Thursday and Friday, with the risk for storms generally increasing as you head north away from the coastline. Severe weather is generally not expected, however an isolated storm or two could have the potential to become on the stronger side. Temperatures should reach the upper 80s for many inland areas during the afternoon hours, and remain right around 70 overnight. Highs along the coast will remain in the mid 80s. Rain chances fade heading into the weekend as a midlevel ridge builds into the area. The presence of high pressure over the Central Gulf will allow the onshore flow pattern to persist, with rain chances dropping to near zero through the weekend and into the early part of next week. Afternoon highs may reach as high as the low 90s across portions of the area, with surface dew points in the upper 60s to lower 70s. Heat index values could have the potential to reach as high as 95. Cady && .AVIATION... (00Z TAF Issuance) Issued at 612 PM CDT Tue Apr 22 2025 Widely scattered shra/tsra activity will diminish this evening as conditions gradually trend from VFR to MVFR this evening and overnight. Meanwhile, tsra activity developing over W Texas may impact our region by tomorrow morning or early afternoon. Confidence is low regarding timing and areal extent of these storms. That being said, we do think there`s a decent chance of at least widely scattered TSRA activity tomorrow morning and afternoon. && .MARINE... Issued at 233 PM CDT Tue Apr 22 2025 Light to occasionally moderate onshore flow will persist through at least Wednesday. A long southeasterly fetch of 15 to 25 knots will develop across the Gulf; resulting in moderate winds and seas up to 6 ft towards the end of the week. Rain and storm chances are expected on Wednesday as a disturbance moves through. Rain chances will gradually decrease into the weekend, with only a few daily showers nearshore and around the Bays. JM && .PRELIMINARY POINT TEMPS/POPS... College Station (CLL) 69 82 69 87 / 10 60 20 60 Houston (IAH) 70 82 70 86 / 10 60 10 30 Galveston (GLS) 73 81 73 82 / 10 40 10 10 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...None. GM...None. && $$ SHORT TERM...Adams LONG TERM....Cady AVIATION...Self MARINE...JM
Area Forecast Discussion
National Weather Service Indianapolis IN
943 PM EDT Tue Apr 22 2025 .KEY MESSAGES... - Warm temperatures through the rest of the week - Shower and thunderstorm chances late Thursday through Friday night - More active pattern setting up next week with better chances for storms && .FORECAST UPDATE... Issued at 941 PM EDT Tue Apr 22 2025 No major changes needed to the forecast with conditions generally evolving as expected. The only minor adjustments have been to dew points which initially were too high compared to observations as some mixing was occurring through the afternoon, but as afternoon mixing has come to an end, dew points have gradually stabilized and started to rise. Rain continues to remain northwest of the forecast area, so will maintain less than 15 POPs through the rest of the early overnight. Fog looks unlikely towards tomorrow morning as Max RH values get to around 85-90 percent, but if any fog does form it looks to be across the northwestern counties along the Wabash Valley where some localized valley fog is possible. With the mostly clear skies and light winds, lows in the upper 40s to near 50 look reasonable, so have not adjusted from the previous forecast. && .SHORT TERM (This evening through Wednesday)... Issued at 211 PM EDT Tue Apr 22 2025 Surface analysis this afternoon shows strong high pressure in place over SW OH and NE KY. Weak southeasterly surface flow was found across Central Indiana. Southerly surface flow was in place across the plains ahead of weak low pressure in SW KS. A weak boundary was found stretching from western IL to northern MO and across KS toward the previously mentioned low. GOES16 shows mainly high CI streaming across Central Indiana and temperatures were quickly climbing toward 70. Aloft, water vapor showed mainly a zonal flow in place. A weak upper wave was producing some rain over WI. Tonight - Zonal flow is expected to continue to stream across central Indiana through at least Wednesday. Little in the way of forcing dynamics is shown to pass during this time. Models suggest the weak boundary to the northwest will remain in place and become more elongated, perhaps stretching into northern Indiana overnight. Light rain was found over IA, pushing east near this boundary. Uncertainty is suggested with the easterly flow of this precipitation as plentiful dry air within the lower and mid levels remains present across Central Indiana. HRRR suggests that some of the precipitation will drift toward Central Indiana but will dissipate upon approach. Perhaps the only locations that could be impacted include Lafayette and Kokomo, but confidence is low. Thus may include some very low pops there tonight, otherwise dry weather will be expected with only high cloud streaming aloft and lows around 50. Wednesday - Dry weather and warmer temperatures are expected on Wednesday as the zonal flow remains in place aloft and a stalled surface boundary remains well northwest of Indiana. This will keep warmer, southerly flow in place across Central Indiana along with warm air advection. Forecast soundings and time heights suggest a dry column through the day. Thus a mostly sunny day with highs in the upper 70s will be expected. && .LONG TERM (Wednesday night through Tuesday)... Issued at 211 PM EDT Tue Apr 22 2025 The long term period features a stretch of above normal temperatures with a few chances for rainfall, mainly on Friday. A more active pattern develops next week with better chances for storms, but continued above normal temperatures. Thursday through Saturday... The pattern going into the weekend resembles more of a May pattern rather than April with above normal temperatures, increasing humidity, and some rainfall and storm chances. The main upper jet will be well to the north, along the US/Canadian border, with a few weak mid level features passing through Indiana Thursday and Friday. At the surface, lower pressure develops along the Front Range while a warm frontal feature stretches through the Plains into the Upper Great Lakes, placing Indiana in an area of warm and moist air advection. A subtle mid level wave passes through Kentucky Thursday afternoon, providing just enough lift to spark off scattered showers and thunderstorms. Not too worried about severe weather as shear and forcing are relatively weak, resulting in mainly single cell pop up convection that falls apart quickly. While most locations in Central Indiana will remain dry, best chance for an isolated shower or storm would be along and south of the I-69 corridor. Expect above normal temperatures Thursday near 80 degrees across Central Indiana within the broad warm sector over the region. Shower and storm chances ramp up early Friday morning for much of the state as a weak area of low pressure and trailing cold front approach from the west. A secondary mid level wave ahead of the main system looks to spark off more widespread convection Friday morning into early afternoon, persisting into the evening as the cold front approaches. Long range ensemble guidance has been consistent with keeping rainfall amounts Thursday - Friday under a half inch for most areas, with the greatest threat at higher amounts in the southern half of Indiana. In these weakly forced, convective regimes, it is easy to get wide ranging rainfall amounts over short distances based on where convection develops or if certain areas get repeated rounds of storms. Overall, the heavy rain threat should be relatively localized, instead of widespread as seen earlier this month. Rainfall and cloud cover will keep temperatures a few degrees cooler than Thursday; however persistent warm air advection should result in temperatures still above average for late April in the low to mid 70s. Chances of convection drop off from northwest to southeast on Saturday as the front moves southeast. Modest cold advection will also bring temperatures closer to normal into the 60s to low 70s. This weekend into early next week... High pressure traverses eastward through the upper Great Lakes this weekend keeping conditions relatively warm and dry for Central Indiana. Cloudy skies post front on Friday night will slowly clear Saturday as easterly flow advects in cooler and drier air. Still expecting temperatures near to slightly above normal on Saturday with highs ranging from the mid 60s in the north to low 70s further south. A warming trend begins again on Sunday as high pressure pushes east and ridging rebuilds over the area. Eyes turn to early next week for the next chance for widespread rain and storms. Longer range guidance has been consistent in showing stronger troughing digging into the Plains Monday and Tuesday setting the stage for storm development upstream. There are still many model discrepancies on how this set up evolves; but confidence is increasing in the storm threat for at least Tuesday. Lower confidence on storms Monday as guidance tries to resolve smaller mid level features ahead of the main system. It is too soon to determine if severe weather will be a threat locally, however it is not out of the question. The pattern remains active through much of next week with additional rain and storm chances likely persisting into the day 8 through 10 timeframe. This pattern supports continued above normal temperatures in the 70s and 80s each day. && .AVIATION (00Z TAF Issuance)... Issued at 646 PM EDT Tue Apr 22 2025 Impacts: - None. Discussion: VFR conditions expected through the TAF period with only some passing thin cirrus aloft. Winds will remain variable at less than 7kts with a predominately southerly direction through tomorrow evening. && .IND WATCHES/WARNINGS/ADVISORIES... None. && $$ UPDATE...White SHORT TERM...Puma LONG TERM...CM AVIATION...White
Area Forecast Discussion
National Weather Service Chicago/Romeoville, IL
Issued by National Weather Service Lincoln IL 859 PM CDT Tue Apr 22 2025 .KEY MESSAGES... - Showers and thunderstorms continue to be in the forecast tonight, with a Marginal Risk for severe storms late this afternoon/this evening. - Well above normal temperatures are expected inland through week`s end, then turning more seasonable for the weekend. - Chances for severe storms return early next week. && .UPDATE... Issued at 858 PM CDT Tue Apr 22 2025 A cluster of thunderstorms looks to move eastward through southern portions of the forecast area late this evening, drawn a bit farther south than expected due to a tongue of MUCAPE up to 500 J/kg per RAP analysis. Will shift PoPs south for the remainder of the evening to account for this. Otherwise, forecast looks on track for tonight, with light winds developing and mostly cloudy skies continuing. NWS Lincoln && .DISCUSSION... Issued at 309 PM CDT Tue Apr 22 2025 Through Wednesday: Zonal flow aloft exists across the area today, with upper level lows across northern MN and Quebec currently. At the surface, a warm front is lifting northeast across northern IL this afternoon...ushering in warmer and more humid air into the area. Expect showers and thunderstorms to move in/redevelop across the forecast area by late afternoon. Believe the greatest threat for storms in the Chicago metro to be from 6 pm to 8 pm this evening. Instability (CAPE of near 1000 J/kg) and shear (0-6 km bulk shear near 30 kts) will provide the risk for some severe storms through this evening. The SPC currently has much of LOT area in a Marginal Risk for tonight (except the SE). Showers and isolated storms will be possible off and on through the night across northern IL, with the best chance for a second round from 3 am to 7 am. For Wednesday, showers and storms will linger in the vicinity of a boundary near the IL/WI border. Expect activity to be mostly in WI, and generally, severe storms are not expected tomorrow. However, some models have CAPEs near 1000 J/kg and deep shear at 25-30 kts, so it`s not out of the question. Currently, northern IL is not outlooked for severe weather by the SPC. Highs tomorrow should be in the mid to upper 70s inland. Knutsvig Wednesday Night through Tuesday: Warm temps will continue through the week with the next weather-maker coming on Friday. Showers and isolated storms are generally expected, with severe storms not expected currently. After a return to cooler temperatures over the weekend, expect a chance for severe storms possibly as early as Monday. Knutsvig && .AVIATION /00Z TAFS THROUGH 06Z THURSDAY/... Issued at 647 PM CDT Tue Apr 22 2025 Key Aviation Messages for the current TAF period: - Periods of scattered showers and thunderstorms through Wednesday morning Showers and thunderstorms are gradually starting to move in from the west along a west-to-east frontal boundary that becomes quasi-stationary through the TAF period. Hi-res guidance continues to depict periods of showers and storms through the TAF window, but that also means that there will be breaks in precip as well which lowers confidence in the exact timing at any given shower/storm. The window for thunder was kept as a PROB30 in the TAFs for the current expectations for storms this evening as well as again tomorrow morning with any adjustments to timing happening tactically. Showers may linger into the afternoon, but generally be on a downward trend as the axis of better moisture shifts north. Winds remain southwest through the night as gusts around 20 knots slowly diminish after sunset. Winds will remain around 10 knots through the day on Wednesday. They are expected to be mostly out of the south-southeast, though there could be a brief window where they flip to the southwest in the afternoon. DK/NWS Chicago && .LOT WATCHES/WARNINGS/ADVISORIES... IL...None. IN...None. LM...None. && $$ Visit us at weather.gov/chicago
Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
618 PM CDT Tue Apr 22 2025 .KEY MESSAGES... - Elevated fire weather conditions across southwest MN through this afternoon. - Wet weather returns to the Upper Midwest Thursday and then again early next week. - Generally above normal in the extended period with highs in the 60s and 70s. && .DISCUSSION... Issued at 243 PM CDT Tue Apr 22 2025 SHORT TERM/ELEVATED FIRE WEATHER... Sunny and clear across the southern half of Minnesota this afternoon, as captured on GOES- East visible satellite. Afternoon highs are on track to reach the upper 60s/near 70 degrees across much of the area. The exception looks to be near Barron, Chippewa, and Rusk counties in Wisconsin where lingering cloud cover has limited heating. For most, the forecast is nice and tame, however we are keeping an eye on the conditions across south/west MN, where fire weather conditions will remain elevated this afternoon. RH`s have dropped below 30 percent across western MN, with winds gusting 25-30 mph. RAP forecast soundings indicate that higher instantaneous gusts, near 35 mph, remain possible given the combination of efficient mixing to 5-7k feet and the presence of a 700mb jetstreak aloft. It`s possible that RH`s dip further, say between 20-25 percent in isolated locations through the late afternoon. A Special Weather Statement for elevated fire weather conditions continues through early evening. NEXT RAIN CHANCES...Nice weather this evening will translate over to a gorgeous Wednesday across much of the region. Afternoon highs are once again forecast to climb into the upper 60s/near 70 for most locations, though it will be slightly cooler northwest of Stearns county in central MN. Of course, it wouldn`t fit the theme of the current unsettled pattern to remain dry for more than a day or two! Warm advection driven showers and a few thunderstorms are possible across southern Minnesota tomorrow night into Thursday morning, with the highest chances along I-90. More significant chances (60-80%) for widespread rain will arrive Thursday afternoon and evening, as an impulse within the large scale southwesterly flow spawns a surface low over the eastern Great Plains. Guidance continues to display the consensus surface low track from roughly central Iowa east towards the Great Lakes. Southern MN/western WI will be north of the surface low, in a region favored for soaking rainfall, supported by healthy moisture advection of PWATs in excess of 1 inch. While the ingredients are in place for widespread rain, a trailing feature in the upper flow will slide over the Dakotas Thursday afternoon. This wave will suppress the forcing over eastern MN/western WI, which unfortunately is likely going to set the stage for another notable precipitation gradient across the area (more rain in eastern MN/western WI, little to no rain across western MN). WPC`s latest QPF outlook displays the potential for 0.75-1" of rain along and east of a line from Martin Co. (MN) to Dunn Co. (WI). Amounts then drop-off a few tenths of an inch with each tier of counties northwest. Should trends continue, fire weather concerns would continue to remain elevated across western MN due to the persistence of dry fuels. As the midnight shift discussed, this could also mean further degradation in the drought monitor across western MN. WEEKEND AND BEYOND...Wet weather moves out of the picture to end the work week and open the weekend. High pressure will keep things dry and quiet Friday and Saturday, with highs in the upper 50s (Friday) climbing into the mid 60s (Saturday). Should be good to go with any outdoor plans! By Sunday, an expansive upper ridge will amplify over the northern CONUS in response to a trough digging in across the southwestern CONUS. Strong southwesterly flow will transport warmer air into the region for Sunday (upper 60s) and Monday (upper 70s!). The trough is forecast to spawn a surface low across the northern Plains that will track from the Dakotas northeast into southern Ontario by Tuesday. Should this track remain relatively steady over the coming days, much of our forecast area will be in the "warm sector" to the southeast of the surface low. In this scenario, widespread soaking rains would develop across northern MN, leaving southern MN/western WI in a region favored for shower/thunderstorm development. It`s too soon to talk specifics with regards to severe weather hazards, however CSU/NCAR ML severe weather probabilities continue to trend upward for Monday. In addition, SPC circled a large portion of southern MN in the Day 7 outlook, given that the pattern is historically favorable for the development of severe thunderstorms. In short, stay tuned! We will have more to share over the coming days. && .AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/... Issued at 614 PM CDT Tue Apr 22 2025 Breezy westerly winds expected to become light and variable after sunset across all sites. Overall flight categories will remain in VFR this period. Some cloud cover is expected to develop as another wave approaches but does not appear to be too much of concern. Model guidance did have some indications of scattered -SHRA accompanying this wave but with confidence below 20 percent, decided against including precip mentions at this time. Winds will veer to the NW tomorrow morning near 10kts after 14-15 timeframe. KMSP...No additional concerns. /OUTLOOK FOR KMSP/ THU...-SHRA/MVFR likely, mainly P.M. Wind NE 10 kts. FRI...VFR. Wind N 10-15 kts. SAT...VFR. Wind SE 5-10 kts. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...None. WI...None. && $$ DISCUSSION...Strus AVIATION...Dunleavy
Area Forecast Discussion
National Weather Service Phoenix AZ
441 PM MST Tue Apr 22 2025 .UPDATE...Updated Aviation Discussion. && .SYNOPSIS... Dry and generally tranquil conditions will persist over the next few days with temperatures running near to slightly above seasonal values. A dry weather system will move off the Eastern Pacific later this week, bringing breezy to locally windy conditions along with a cooldown with temperatures falling below seasonal normals into the weekend. && .DISCUSSION... 500mb RAP analysis reveals weak quasi-zonal flow stretched out across much of the Great Basin, resulting in a fairly quiet pattern for the region. With the expectation that this pattern will not vary much over the next few days, very little day-to-day changes will take place at least through the middle of the week with dry conditions prevailing and lower desert highs ranging in the upper 80s to lower 90s. Global models show a very weak disturbance moving through the western CONUS through the middle of the week, but the only noticeable impact with this would be the presence of breezy to locally windy conditions in the typical spots of Western Imperial County. Ensembles have come into a bit more agreement regarding the stronger area of low pressure later this week compared to 24 hours ago. Some subtle differences remain, mainly in the timing, exact track, and amplification, but it appears that the models have honed in on an evolution that takes the center of this system across the Southern Great Basin by Sunday. Though this system appears to be dry, translating to essentially zero rain chances, it will not be without its noticeable impacts on regional conditions. Associated height anomalies approaching 1.5-2 standard deviations below normal vs. climatology will translate to a decent cooling trend heading into this weekend. Even though NBM MaxT spread remains around five degrees during the weekend timeframe, this does not degrade the idea that regionwide cooling temperatures are likely, with many areas potentially falling 5-10 degrees below normal for late April. The other associated impact will be an increase in winds during much the weekend, particularly during the afternoon and evening hours, thanks to an enhancement of the thermal and pressure gradients. The magnitude of the winds will be largely dependent on the track of the system, but early indication are that gusts upwards of 25-35 mph may be common, with advisory level gusts >=40 mph possible for the usually windy spots of Southeast California and the Arizona high terrain. We are several days from this low moving onshore so forecast detail could certainly change, but if trends continue in the direction they are, wind products may be needed later this week. Regardless of if winds do reach advisory thresholds, the relatively warm and dry airmass in place, combined with the enhanced winds, will result in periods of elevated, to potentially critical fire weather conditions at times. && .AVIATION...Updated at 2340Z. South Central Arizona including KPHX, KIWA, KSDL, KDVT and Southeast California/Southwest Arizona including KIPL and KBLH: No aviation weather concerns under clear skies can be expected throughout the TAF period. The overall wind pattern will continue to exhibit the typical diurnal tendencies with overall speeds aob 10 kts. There will likely be periods of light variability to even calm conditions, especially during the diurnal transition. Southerly winds are expected for a few hours mid to late morning Wednesday at the Phoenix terminals before veering toward a W/SW component. Breeziness will pick up around the region heading into tomorrow afternoon with gusts to around 20 kts possible at times. && .FIRE WEATHER... Dry and tranquil weather conditions will persist through much of the remainder of the workweek, with slightly above normal temperatures. MinRH values each day will bottom out near 10% areawide with poor to fair overnight recoveries. Fairly light and diurnally driven winds are expected through at least Thursday, with some afternoon upslope breeziness. Winds are likely to increase by the end of the week into this weekend as an upper level low pressure system moves into the western United States. This may lead to locally elevated fire weather conditions, particularly for the high terrain east of Phoenix during the weekend, though temperatures will cool to slightly below normal. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...None. CA...None. && $$ DISCUSSION...RW AVIATION...Smith/Lojero FIRE WEATHER...Whittock
Area Forecast Discussion
National Weather Service Raleigh NC
826 PM EDT Tue Apr 22 2025 .SYNOPSIS... A backdoor cold front will approach from the north overnight tonight, then move through the Carolinas on Wednesday. The front will stall and weaken over the Savannah Basin through the end of the work week, while high pressure will otherwise build across and offshore the middle Atlantic. && .NEAR TERM /THROUGH TONIGHT/... As of 826 PM Tuesday... Convection has really weakened and dissipated in the last hour or two. The combination of the eastward progressing outflow from earlier storms and loss of daytime heating are likely contributing factors in the weakening trend of storms. The outflow from earlier convection lies along the central Coastal Plain into the eastern Sandhills, with the sea-breeze boundary currently colliding with the outflow. Convection was largely located over the Sandhills to Coastal Plain. Surface analysis reveals the cold front is loosely draped to our northwest, across northwest and north-central VA, with 1020 mb high pressure over the lower OH valley. Had to adjust PoPs quite a bit given the CAMs were about 2-3 hours slow compared to reality. A few more hours of isolated to scattered storms are possible over the Sandhills to central Coastal Plain, but outside of that we should turn very quiet with limited shower chances through late evening to the early overnight hours with stability behind the outflow and mid-level energy pushing toward eastern NC. Some of the latest runs of the HRRR suggest additional isolated or scattered showers or storms could redevelop as the backdoor front slides south from the north and east, affecting areas north and east of the Triangle. The favored areas may end up being the northern to central Coastal Plain, though confidence is low on coverage. But given weakly unstable and the convergence along/ahead of the front, this seems plausible. Have low-end chance PoPs for this overnight, in which isolated storms could reach the southern Coastal Plain by daybreak as the front continues to slide southward. Though the signal is not very strong in the guidance, cannot rule out some patchy fog, mainly along/south of US-64 ahead of the southward moving front. Expect lows ranging from the upper 50s N and W to the low to mid 60s in the SE. && .SHORT TERM /WEDNESDAY AND WEDNESDAY NIGHT/... As of 245 PM Tuesday... The cold front will be moving southward through the region Wednesday morning before stalling to our south. Throughout the day, isolated to scattered showers with embedded thunderstorms are possible with the front. PWATs are still showing values around 1.4-1.5 inches across the region, therefore as diurnal heating increases throughout the afternoon, chances of convection will increase. The greatest chances of showers or storms developing is to the south where the greatest forcing from the stalled front will be located. CAMs are showing very little shower activity across the region, so kept the region in slight chance to chance PoPs, with the greatest probabilities to the south. The chance of any showers being severe is currently low as shear and instability should be weak. With the increased cloud cover and cold fropa, high temperatures should be near to slightly above normal, or in the mid 70s to around 80. Minimum temperatures should be in the mid 50s in the northeast to the low 60s in the south. && .LONG TERM /THURSDAY THROUGH TUESDAY/... As of 245 PM Tuesday... * Showers and potential thunderstorms are expected everyday through Thursday The cold front should stay stalled to our south on Thursday before moving north through the region on Friday as a warm front. The chance of showers with the potential of embedded thunderstorms continues on Thursday and Friday where the frontal boundary lines up with diurnal heating and mid-level perturbations in the flow. Thus, rain and storm chances are maximized in the afternoon and evening each day. Rain chances will continue Saturday afternoon through evening, as another cold front approaches the region from the west. Maximum temperatures Thursday through Saturday should be about 5 degrees above normal on average, with highs generally expected in the mid 70s to low 80s. The warmest day should be on Saturday with temperatures in the mid 80s in the south. Minimum temperatures should be about 10-15 degrees above normal, with lows in the upper 50s to low 60s nightly through Saturday night. The cold front should move through the region early Sunday morning, dropping high temperatures into the low to mid 70s Sunday afternoon, with lows dropping into the mid 40s to low 50s. Monday and Tuesday should both warm as a surface high builds behind the front. && .AVIATION /00Z WEDNESDAY THROUGH SUNDAY/... As of 815 PM Tuesday... Scattered showers are expected to continue tonight. There may be some brief MVFR conditions with a shower. Otherwise, a backdoor cold front and following NE flow will then result in a chance of MVFR ceilings late tonight into early Wednesday morning. Additional scattered showers are expected, mainly in the afternoon. Outlook: NE flow behind a backdoor cold front will result in periods of mainly MVFR ceilings through Fri, with a chance of IFR ones during the morning Thu and Fri. The nely flow will also shift rain/thunder chances south to mainly FAY Wed-Thu, then area-wide ahead of and along the next cold front Fri-Sat. && .CLIMATE... Record High Minimum Temperatures: April 22: KGSO: 63/1967 KRDU: 66/1909 KFAY: 64/1963 && .RAH WATCHES/WARNINGS/ADVISORIES... None. && $$ SYNOPSIS...Kren/MWS NEAR TERM...Kren SHORT TERM...Helock LONG TERM...Helock AVIATION...PWB/MWS CLIMATE...RAH