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

Area Forecast Discussion
National Weather Service Bismarck ND
944 PM CDT Wed May 4 2022 .UPDATE... Issued at 943 PM CDT Wed May 4 2022 Quiet weather continues. No major changes needed at this time. UPDATE Issued at 657 PM CDT Wed May 4 2022 For early evening update only change was to add some fog over the James River Valley. HRRR has been consistent with suggesting some may form, and plenty of low level moisture will be in place. With that said, do not expect coverage to be rather low, so will go with patchy wording. && .SHORT TERM...(This evening through Thursday) Issued at 302 PM CDT Wed May 4 2022 More days of beautiful spring weather to come with highs in the 60s and 70s. Surface high pressure off to the east and a shortwave ridge aloft continues to affect the area, leaving winds from the south and dry weather. Mostly clear skies in the west and north will continue through Thursday. While high cirrus clouds continue to stretch across the south. A thermal ridge at 850mb will start to creep into the west tonight, keeping lows above freezing in the mid 30s to lower 40s. High temperatures Thursday will be warmer because of this thermal ridge, with most of the west reaching into the low 70s. The east will see temperatures in the mid 60s, and the south wind will continue across the area as well. Late thursday evening, flow aloft starts to turn to the southwest with a broad trough approaching, beginning our chances of showers for the weekend and next week. .LONG TERM...(Thursday night through Wednesday) Issued at 302 PM CDT Wed May 4 2022 The warmest temperatures of the week and an active wet pattern are the highlights of the long term period. The aforementioned thermal ridge will continue to affect the area along with southwest flow aloft Friday. Leading to highs in the upper 60s east to low 70s west. A shortwave trough axis and associated cold front will move through Friday afternoon. This will be the first round of possible showers and a few thunderstorms. Thunderstorms are mostly likely in the west and central. Timing on these are likely to be Friday afternoon through about midnight. The next round of showers looks like Saturday, when a Northern Rockies low pressure moves into the Dakotas through Sunday night. Uncertainty still exist with these systems, the cluster analysis shows uncertainty in the timing the broad trough evolving to the east. The potential for thunderstorms is much higher on Saturday than Friday, even a small potential for severe storms through the evening. Again, lots of uncertainty with this. Temperatures on Saturday could reach into the mid 70s in central North Dakota. NBM temperatures spreads for the weekend have decreased a little, increasing some confidence in these temperatures. Winds on Saturday look to be breezy, with a tightening of the pressure gradient from the incoming low pressure system. Sunday temperatures cooldown some with northerly winds on the backside of the low. The west could get breezy on Sunday with these winds bringing in cooler air and a isallobaric gradient. Chances for rain continue into Sunday morning and then again late Sunday evening. The train of low pressure systems continue early next week with another Northern Rockies low moving through the Dakotas on Monday. Southwest flow aloft still continues through this long term period. Temperatures will most likely remain on the cooler side through Wednesday, with highs in the 50s and 60s. The 72 hour QPF ending Tuesday morning will mostly likely be between 0.25 and 1 inch. Probabilities for greater than 0.25 are 80 percent, and drop to 30 percent for 1 inch across the area. Tuesday night surface high pressure and a shortwave ridge aloft build in. Then southwest flow aloft builds back in Wednesday afternoon, and so does the chance for showers in the northwest. && .AVIATION...(For the 00Z TAFS through 00Z Thursday evening) Issued at 657 PM CDT Wed May 4 2022 Patchy fog possible late tonight into early Thursday over the James River Valley, possibly affecting KJMS. Have not mentioned it in the TAF at this time as coverage and confidence in it forming are rather low. Otherwise, VFR conditions will prevail. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...JJS SHORT TERM...Smith LONG TERM...Smith AVIATION...JJS
Area Forecast Discussion
National Weather Service Birmingham AL
705 PM CDT Wed May 4 2022 .UPDATE... Evening Update and 00Z Aviation. && .SHORT TERM... /Updated at 0652 PM CDT Wed May 04 2022/ No major changes planned in the short term. Isolated thunderstorms were ongoing near a pre-frontal trough north of the I-20 area. Earlier this afternoon, some of the storms were strong to severe with some hail being reported. Overall moisture is limited this evening and the best Bulk Shear west of the area. Therefore, expect the storms to largely remain below strong to severe limits and slowly diminish through around 10 pm. Low temperatures will be mild and in the 60s area wide. The best isentropic lift shifts westward as the quasi-stationary boundary remains across northern Alabama. This will provide the best low cloud and fog development to our south and west. But again, some of the fog and low clouds may affect southern areas for a few hours near sunrise. 75 Previous short-term discussion: /Updated at 1244 PM CDT Wed May 04 2022/ Through Thursday. The surface front has now stalled out across the Tennessee Valley, stretching southwestward into the ArkLaTex early this afternoon. A few showers are starting to develop just south of the boundary across our northern most counties, and we`ll see convective activity increase through the afternoon. Conditions are very warm and fairly muggy across much of the region this afternoon, with temps rising into the mid and upper 80s with dewpoints in the mid and upper 60s. SBCAPE values based on RAP analysis are indicating at least 3000 to 4000 J/kg, so we`ll certainly see some summer- like convective activity with the added trigger of the stalled surface front. However, temperatures aloft this afternoon are warmer than they were yesterday and we don`t have the shear aloft. Still, we do have a good bit of dry air aloft and DCAPE values currently analyzed around 1000 J/kg. Therefore gusty winds are certainly possible if we can get a higher updraft with the unstable and moist airmass currently in place, much like we would during a typical summer day. I`ve kept PoPs in the chance category this afternoon as most activity should remain scattered in nature, gradually diminishing during the evening. High-res guidance is indicating yet another opportunity for low clouds and fog forming generally along and south of the US 80/I-85 corridors just before daybreak on Thursday. We`re not currently anticipating as much low clouds or fog that we observed this morning, but we`ll still have to monitor for the possibility of one mile or less visibilities across our southern tier of counties. The stalled surface front will quickly lift northward and southerly flow will return during the afternoon on Thursday. Ridging aloft will keep convective development to a minimum until later on into the evening closer to the next approaching storm system to our west. Rain chances will remain low until later into Thursday evening when a convective complex is poised to move into Mississippi and northwest Alabama that could give us our next chance of marginally severe storms that we`ll have to keep an eye on. Current guidance trends are continuing to indicate that the MCS will gradually weaken as it moves into our area between 7pm and midnight, but the possibility of an isolated damaging wind gust and quarter size hail will remain in the forecast for now. 56/GDG .LONG TERM... /Updated at 0336 PM CDT Wed May 04 2022/ The only time frame of concern in the extended is Thursday night and Friday, which is what we will focus on with this updated discussion. The weekend and beyond looks warm and dry. As far as the grids themselves go, only minor adjustments were made to pops. The overall severe parameter space remains very similar to what was detailed in the previous long-term discussion, so will focus more on the changes to the threat areas and timing. Despite some discrepancies, most models show an MCS crossing into northwest Central AL sometime between 7p and 10p and quickly dissipating. Therefore, we were able to narrow the severe threat window from 12 hrs to around 6 hrs for Thursday night. The decaying MCS will leave a boundary across the area, perhaps near the I-59 corridor, Friday morning. The presence of additional boundaries is highly possible. Although thunderstorm redevelopment is possible area wide by mid morning Friday, the best chance of strong to severe storms appears to be south and east of the old MCS outflow boundary during the afternoon. The main threats will be damaging wind gusts and large hail. 19 Previous long-term discussion: /Updated at 0408 AM CDT Wed May 04 2022/ Thursday night through Tuesday: Tricky/complicated convective forecast for Thursday night and Friday, with multiple potential rounds of strong to severe storms possible, each round dependent on what happens with the round preceding it. An upper low embedded in a potent low amplitude trough will move across Kansas and Oklahoma on Thursday, reaching the Mid- Mississippi Valley by Friday morning while now potentially beginning to take on a bit of a negative tilt, and then moving through the Ohio Valley on Friday night. Plentiful upper-level diffluence will be present ahead of it, while a 50-60kt mid-level jet will be located along its southern flank. At the surface, low pressure will move northeastward from Oklahoma to western Missouri on Thursday, then eastward to Indiana by Friday night. A cold front will reach the ArkLaMiss Friday morning and Central Alabama by Friday afternoon, with a 35kt southwesterly LLJ ahead of it. A pre-frontal MCS is forecast to develop across the ArkLaMiss Thursday afternoon in association with a lead shortwave. There`s quite a bit of spread in late range CAM guidance valid at 7pm Thursday, with placement of the leading edge of the MCS outflow ranging from just west of the MS/AL state line to still west of the Mississippi River. This MCS is expected to weaken/eventually dissipate later Thursday night as it gets ahead of the forcing and enters some drier air that will be across Central Alabama Thursday afternoon, but could pose at least a marginal threat of severe weather across the northwest half of Central Alabama Thursday night with supportive bulk shear values and lapse rates. Attention then turns closer to the shortwave and front during the pre dawn hours Friday morning across Mississippi, where either a new MCS could form or there could be some reintensification of the southern part of the old MCS. This is then forecast to move across much of Central Alabama Friday morning. Dew points increasing to near 70F and continued steeper lapse rates aloft will result in relatively higher end CAPE-bulk shear parameter space developing even by mid-morning with MLCAPE values of 1500 to 2000 J/kg and 0- 6km bulk shear values of 45 to 55 kts resulting in damaging winds and large hail. But this will be conditional on the air mass not being contaminated by outflow from prior MCS activity. Finally, some guidance indicates scattered storms redeveloping along the front within the mid-level dry slot Friday afternoon. While this would be unlikely earlier in the spring, it would at least be within the realm of plausibility with May heating. Will indicate a slight risk areawide all day on Friday, with any later upgrades dependent on mesoscale trends. Have also increased the hail threat to ping pong ball size based on the CAPE/shear space; if some cellular activity develops some stones larger than that would be possible. Overall, the veered and modest LLJ results in 0-1km SRH values only around 100 to 150 m2/s2. Will note that some guidance indicates some higher values, but behind the main line Friday morning. The potential for an isolated tornado is low but may be non-zero with any mesovortices or supercell-boundary interactions and will continue to monitor mesoscale trends. An omega block looks to develop behind this system, with Central Alabama in the ridge portion of the block. After a slight cooldown over the weekend at least as far as overnight lows are concerned, hot and dry conditions should return for next week. 32/Davis && .AVIATION... 00Z TAF Discussion. Other than short duration MVFR/IFR ceilings/vis, VFR conditions will be observed a majority of the time. Convection this evening should remain north of the terminals and do not have any mention before the storms diminish in a few hours. The best chances for any restrictions will be south and west, but have a short duration at least MVFR vis mentioned at several terminals. Winds become light and variable. On Thursday, there is a lesser chance for convection due to a short wave ridge moving over the area. This should largely inhibit convection. Winds become southwest around 10kts and may gust to near 20kts at times here and there. Note: AMD NOT SKED at ASN due to unavailable observations. 75 && .FIRE WEATHER... A relatively moist and unstable air mass remains in place for the remainder of the work week with rain chances increasing area wide Thursday night and Friday. Patchy fog is possible early Thursday morning, especially south. Minimum relative humidity values will remain at or above 40 percent today and Thursday. 20ft winds keep a westerly component today, up to 6mph, and become southerly Thursday, at 6-10mph. Better rain chances move across all of Central on Friday along and ahead of a front. && .PRELIMINARY POINT TEMPS/POPS... Gadsden 61 89 64 81 57 / 20 20 40 90 30 Anniston 64 89 66 81 60 / 20 10 30 90 30 Birmingham 66 90 67 82 60 / 20 10 40 90 20 Tuscaloosa 67 90 67 84 60 / 20 10 50 80 20 Calera 67 89 68 83 62 / 20 10 30 90 20 Auburn 67 89 66 81 63 / 0 10 10 80 30 Montgomery 67 90 68 85 64 / 0 10 10 80 20 Troy 67 91 67 84 65 / 0 0 10 80 30 && .BMX WATCHES/WARNINGS/ADVISORIES/... None. && $$
Area Forecast Discussion
National Weather Service Denver/Boulder CO
821 PM MDT Wed May 4 2022 .UPDATE... Issued at 816 PM MDT Wed May 4 2022 The upper level low will move from south central CO into sern CO overnight. Showers were affecting the Palmer Divide into srn Lincoln county while another batch of showers were near the CO-WY border. This activity was tracking south and will move across the the I-25 Corridor thru midnight. Meanwhile activity over the mtns has generally ended so will cancel the advisory that was in effect for zn 33. Finally, there still could be some fog overnight, however, if clouds linger that may prevent it from becoming widespread over the plains. && .SHORT TERM...(This evening through Thursday) Issued at 225 PM MDT Wed May 4 2022 Water vapor imagery shows a cut-off trough over the San Juan mountains with southeasterly mid to upper level flow over our area. There are a few showers and storms developing over the southern foothills and Park County this afternoon as an area of enhanced QG ascent moves overhead with weak instability. Snow levels in that area are around 7500-8000 feet and higher elevations will receive a couple inches of additional snow accumulation. This precipitation will continue over that area into the early evening before the QG ascent and instability decreases. Farther north over the northern foothills and northern I-25 corridor, there has been some clearing this afternoon. Somewhat surprisingly, FNL reached 55 degrees this afternoon and this clearing has allowed weak instability to form with up to 500 j/kg of CAPE. This weak instability along with light upslope flow and weak convergence will create a few showers and storms initiating in Larimer County late this afternoon and moving southward through the Denver metro this evening. The HRRR seems to overestimate the precipitation out of these showers while the NAM underestimates the precipitation. A blend of the short range models was used with 0.1 to 0.25 QPF totals expected through midnight tonight. The snow level will be around 7500 feet and another couple inches of snow may accumulate over the higher ridges. The trough will depart our forecast area late tonight as it will reach Kansas around sunrise. There will be some QG ascent on the northwest side of the trough over far eastern Colorado late tonight and early tomorrow morning that may allow for some light rain showers to persist. In addition, there will be some lingering moisture in the mountains that may allow for a few snow showers to continue overnight and into early tomorrow morning. The only other weather concern will be the potential for fog across the urban corridor and eastern plains. The healthy amount of moisture along with cool conditions may allow for some fog development. The exact location of this fog will be dependent on the location of the rain but the most likely areas for fog would be the Palmer Divide and the South Platte River Valley. Some fog was added to the forecast but it may need to be modified this evening. By the late morning Thursday, subsident flow will move over our forecast area which will clear out the precipitation and clouds. Sunshine and weak warm air advection will allow highs to warm closer to normal but they will still be below normal values. There are no other weather concerns as it should be a very nice spring day .LONG TERM...(Thursday night through Wednesday) Issued at 250 PM MDT Wed May 4 2022 ...DRY WEATHER RETURNS... We`ll quickly return to a dry weather pattern through at least early next week, as the weather pattern will feature persistent moderate to strong west/southwest flow. Friday will feature warmer temperatures with light to moderate west/southwest flow aloft, warm advection, and weak lee troughing. That should boost high temperatures into the lower 80s across the plains. Saturday will be even warmer with continued warm advection, stronger west/southwest flow aloft, and stronger lee troughing. That will also support windier conditions over the forecast area, and return to more significant fire weather conditions - see Fire Weather section below. The increase in winds will occur as a fast moving short wave moves across the Northern Rockies. Highs should be able to push into the mid 80s across all of the plains Saturday. That short wave to our north should be enough to at least push a cold front across northeast Colorado Saturday night, with a brief respite in winds and full mixing into Sunday. However, by late in the day we can`t rule out a redevelopment of gusty winds due to the strength of flow aloft and potential for lee troughing. The same weather scenarios may play out for Monday and Tuesday, as it will be very hard to time these lulls in wind/backdoor cold fronts through early next week. There has definitely been a trend to stronger upper level ridging over us through at least next Wednesday, keeping us mainly dry and mild through this entire period. At this time, looks like the only threat of precipitation will be late Saturday and then again on Sunday with the proximity of the upper level trough, but any precipitation would be very light and mostly confined to the high country. && .AVIATION...(For the 00Z TAFS through 00Z Thursday evening) Issued at 518 PM MDT Wed May 4 2022 IFR ceilings will continue but could see some improvement by 10z as MVFR ceilings occur. May see a few showers drift across thru 03z. At this time believe probability of fog will be low overnight. Winds will be light and may go to light drainage after 06z. Ceilings should light Thu morning with winds becoming north by late morning. && .FIRE WEATHER... Issued at 250 PM MDT Wed May 4 2022 Fire weather conditions will become elevated again by Friday, especially over the southern Front Range Foothills, Palmer Divide area, and South Park. Those conditions would likely become critical Saturday and Sunday with stronger winds, warmer temperatures, and lower humidity. Wind gusts of 40-50 mph may develop in southwesterly wind prone areas of the foothills and Palmer Divide, with minimum humidity of 10-15%. Those conditions may improve slightly at times Sunday, Monday, and Tuesday, depending on timing and potential of weak backdoor cold fronts to slip across the plains. The southern portions of our forecast area from southern Jefferson County through Douglas, Elbert, and Lincoln Counties is where we`ve had less precipitation lately (about 0.50 inch over the last 10 days) and probably a slower/minimal green-up. However, another quarter to half inch would be possible in those areas through tonight, so something to watch that could be beneficial. Farther north across the rest of the forecast area, we`ve had more precipitation averaging closer to 0.8-1.5 inches, with 1.5-2 inches in the northern Front Range Foothills and far northeast corner. That should promote a stronger green-up and less fire danger. We`ll need to coordinate with land managers to assess the green-up and potential need for Fire Weather highlights this weekend into early next week. && .BOU WATCHES/WARNINGS/ADVISORIES... && $$ UPDATE...RPK SHORT TERM...Danielson LONG TERM...Barjenbruch AVIATION...RPK FIRE WEATHER...Barjenbruch
Area Forecast Discussion...UPDATED
National Weather Service Brownsville TX
615 PM CDT Wed May 4 2022 .DISCUSSION...Updated for latest aviation discussion below. && .AVIATION...Southeasterly winds continue to gust this evening but expected to decrease over the next few hours. In the meantime VFR ceilings at MFE and HRL will fall to MVFR once again this evening into the overnight, while BRO has already fallen to MVFR. Winds will pick up once again on Thursday, with VFR returning by late morning to all aerodromes. && .PREV DISCUSSION... /issued 257 PM CDT Wed May 4 2022/ SHORT TERM (Now through Thursday Night): Another warm, windy, and humid day in progress for the Rio Grande Valley. Have been able to squeak by without a Wind Advisory (30mph sustained and/or 40mph gusts), but it`s been close at times, so opted for a Special Weather Statement. Amount of cloud cover and more SE vs. SSE wind direction have likely helped to keep speeds down just a bit, along with a pretty stout inversion with a base around 2,000-2,200 ft., per 12Z BRO sounding. Not really a lot of change expected in the next 24-36 hours. Model guidance continues to trend north of the area with most any evening/overnight convection trying to move in off the Sierra Madres in Mexico. HRRR still hinting at the possibility of a few showers or even a brief thunderstorm moving across the Northern Ranchlands overnight, so have kept that possibility in the forecast. An unfavorable environment in the mid-Lower RGV, with rather dry air between 850-700mb, should preclude shower activity in the urban corridor. With an upper-level low and associated surface feature only slowly moving across CO/KS by tomorrow morning, a decent pressure gradient is maintained overnight, with winds staying elevated to around 15mph. This, in turn, should keep Thursday morning lows the mid-upper 70s for all, about 5-7 degrees above average. 70-80 knot zonal flow at 250mb should produce more breezy winds (at least through around mid-day) and temps a couple of degrees hotter than today, especially west of Hwy. 281/I-69C where models hint at a weak wind-shift (dryline remnant?) drifting down in the afternoon. Dewpoints may "dip" into the upper 60s F behind this feature, but current forecast still indicates heat indices topping out at 105- 108F from western Hidalgo, across Starr, and into southern Zapata counties. NAM/GFS both hinting at a weak vort lobe passing through or across the area late Thursday night. With moisture appearing very shallow in time-height sections, it may not be able to produce much more than nocturnal "streamer" type showers, at best. Inserted some silent 10% PoPs to cover this. As winds go slack, the humid airmass could yield some patchy fog across mainly Brooks and Kenedy counties late Thursday night/early Friday morning as well. LONG TERM (Friday through Wednesday): Looking ahead at the weekend into early next week, HOT continues to be the name of the game for Deep South Texas...thank you May, onshore winds, mid level ridging and the Omega Block heading our way. Mid level ridging begins to set up over the northwest Gulf of Mexico this weekend, helping to preclude rain chances and keep temperatures above normal through the period. Highs will easily reach the triple digits across most of Deep South Texas, except for the Mid to Lower Valley and coastal locations Saturday and Sunday...and maybe even Monday. Record highs may be tied or even broken at some locations this weekend! But the real kicker will be the heat indices, or "feels like" temperatures...making Heat Advisory conditions possible (heat indices 111+ degrees) Saturday, Sunday, and Monday. An Omega Blocking pattern will set up across the country by the end of the weekend with deep ridging over Deep South Texas along with the rest of the central part of the country, and mid level lows forming over the East Coast and West Coast. This pattern will continue to keep Deep South Texas and the Rio Grande Valley hot and rain free into midweek next week. However, deepening low level moisture will increase cloudiness Tuesday and Wednesday, helping to knock highs down a few degrees (even though they`ll still remain well above normal). MARINE: Now through Thursday Night..Small Craft Advisory (SCA) for all coastal waters issued by previous shift seems to be on track, so will not make any changes at this time. SCA on the Laguna Madre is scheduled to end at 10pm, though Small Craft Exercise Caution (SCEC) conditions likely to continue much of the night. Current obs from Buoy 42020 indicate SE winds right around 20 knots, which should only edge up into the night. Current seas around 5 ft. should build a bit more as well. SCA on the Gulf waters currently out through 7 AM Thursday may need to be extended into mid-day, but will let following shifts make that call. Conditions improve somewhat for Thursday afternoon/night but SCEC likely to continue. Friday through Tuesday...On Friday, winds will relax a little bit and seas will continue to gradually fall, but it will only be a short reprieve before winds and seas pick up this weekend, with SCEC conditions or low-end SCA conditions likely by Saturday recreational boaters and surfers stay tuned to take advantage of a nice day on the water this Friday. Seas will continue to build into early next week with the persistent elevated south- southeasterly flow across the waters, making SCEC and even SCA conditions possible through the rest of the period. && .PRELIMINARY POINT TEMPS/POPS... BAYVIEW/PORT ISABEL 77 89 76 91 / 10 0 10 0 BROWNSVILLE 78 91 77 94 / 10 0 10 0 HARLINGEN 77 93 76 96 / 10 0 10 0 MCALLEN 77 96 76 98 / 10 0 10 0 RIO GRANDE CITY 76 100 75 100 / 20 10 10 0 SOUTH PADRE ISLAND 76 82 77 82 / 10 0 10 0 && .BRO WATCHES/WARNINGS/ADVISORIES... TX...None. GM...Small Craft Advisory until 10 PM CDT this evening for GMZ130-132- 135. Small Craft Advisory until 7 AM CDT Thursday for GMZ150-155-170- 175. && $$ This product is also available on the web at: 68-McGinnis/Aviation
Area Forecast Discussion
National Weather Service Cheyenne WY
606 PM MDT Wed May 4 2022 .UPDATE... Issued at 606 PM MDT Wed May 4 2022 Snow has begun to decrease across the Sierra Madres and Snowy Range. As a result, allowed the winter weather advisory to expire. && .SHORT TERM...(Late this afternoon - Friday) Issued at 315 PM MDT Wed May 4 2022 Mid/upper level Pacific low pressure center was nearly stationary over west central CO this afternoon. An inverted surface trough extended north from a surface low over northeast NM along the WY/CO Front Range. Abundant moisture was lifting northward and wrapping around the backside of the CO low. Scattered rain and snow showers were developing and spreading north to northwest along and west of the I-25 corridor. Limited insolation has prevented thunderstorm development thus far, but cannot rule out isolated coverage through late afternoon. Temperatures ranged from the upper 30s to lower 50s. Prevailing winds were variable less than 10 kt. The CO low is forecast to track slowly eastward through tonight and be located over western KS Thursday morning. Ample moisture and lift from this system will continue to produce scattered rain and snow showers, tapering off from northwest to southeast late tonight and early Thursday morning. Elevations above 8500 feet can expect an additional 1 to 3 inches through this evening. Impacts should be limited though, and the Winter Weather Advisory will be allowed to expire at 6 PM this evening. A shortwave mid/upper level ridge will translate east through southeast WY and western NE Thursday afternoon and evening in advance of an approaching shortwave trough from the northwest. This trough will track east across MT and northern WY into the Dakotas Thursday night and Friday. Westerly 700-800mb flow will increase to 50-55 kt Friday morning, with CAG-CPR 700/850mb gradients rising to near 50 mtrs. Our in-house random forest high wind probabilities for ARL have increased to 50 percent. It`s looking like a marginal high wind episode for the WY Zone 110 between 12Z and 21Z Friday. Conditions are not as favorable for the I-80 Summit and Bordeaux. Not anticipating high wind headlines at this time, but later shifts will need to monitor model trends. After a couple days of unseasonably cool days, Thursday will begin the warming trend as 700mb temperatures approach 5 degrees Celsius in the afternoon. High temperatures outside the mountains will be near seasonal normals in the 60s. Increasing westerly downslope winds will add another 10 to 15 degrees to Friday`s afternoon high temperatures. .LONG TERM...(Friday Night - Wednesday) Issued at 431 AM MDT Wed May 4 2022 The extended forecast period begins with warm & dry conditions for the first half of the weekend as short wave ridging persists ahead of a deepening upper-level trough over the northwestern CONUS. The GFS/ECMWF/GEM remain in good agreement with H7 temperatures around +7 to +9 deg C roughly along and southeast of a line from Cheyenne Wyo to Chadron Neb at 00z Sunday. Believe the majority of the mid/ upper-level cloud cover during the day will be confined further to the north, closer to the stronger jet energy aloft. 00z GEFS plume data has come in slightly cooler than earlier runs, but still does show 50th percentile values over +8 deg C at H7 which suggests the potential for a very warm day. Have hedged between the 75th & 90th percentile of the NBM for highs on Sunday. Convective chances will likely increase by late Saturday afternoon and early evening as SW flow aloft increases ahead of the next disturbance. Guidance still shows the best moisture return and resultant CAPE exceeding 1000 J per Kg over central Nebraska, so strong/severe storms are unlikely though not entirely out of the question if the surface low manages to organize further west than current guidance suggests. Unsettled weather returns Sunday through the middle of next week with active southwesterly flow in advance of western US troughing. Overall not a particularly cold pattern in this flow regime, but daily chances for precipitation will exist for much of the period w/ rain as the dominant precipitation type for lower elevations. && .AVIATION...(For the 00Z TAFS through 00Z Thursday evening) Issued at 531 PM MDT Wed May 4 2022 Very limited confidence in this TAF issuance, especially with regards to ceilings and visibilities. Latest radar loop was showing rainfall starting to become more widespread over northwest Laramie county. This rainfall should gradually shift east to KCYS early this evening. The biggest question will be what happens after the showers end this evening. If KCYS does clear out after the rain ends, it may cause visibilities to drop in a hurry. However, northwest flow and subsidence is also expected to build into the area which may limit the fog potential. The HRRR is leaning in this direction, and will tend to follow for now. Elswhere, there is a lot of uncertainty on what areas will clear out this evening. We will play things conservative route for now, and keep ceilings in the MVFR category. && .FIRE WEATHER... Issued at 230 PM MDT Wed May 4 2022 Fire weather concerns will be low. A Pacific low pressure system over west central Colorado will continue to produce occasional rain and snow showers as it slowly moves east through Thursday morning. Warmer, drier and breezy weather is forecast Thursday afternoon through Saturday. Minimum relative humidities will range between 20 and 30 percent. Cooler temperatures with chances for showers and isolated thunderstorms Sunday and Monday. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...None. NE...None. && $$ UPDATE...MRD SHORT TERM...MAJ LONG TERM...CLH AVIATION...REC FIRE WEATHER...MAJ
Area Forecast Discussion
National Weather Service Wichita KS
652 PM CDT Wed May 4 2022 .SHORT TERM...(This evening through Friday night) Issued at 226 PM CDT Wed May 4 2022 Current satellite water vapor imagery shows a vigorous shortwave over the Rockies, with this shortwave expected to move east into the plains tonight through Thu. Warm advection and low level moisture transport has led to, off and on, showers and embedded thunderstorms across southern KS, with the latest RAP showing persistent moisture transport. Rich Gulf moisture associated with this moisture transport has led to very efficient rainfall producers with some areas already picking up 0.5 to 0.75 inches of rainfall. Could see a slight lull in the moisture transport for the early afternoon hours, before its ramps back up this evening and especially after midnight. When it comes to severe weather potential, looks like the warm sector and warm front will stay well south of the area, situated closer to the Red River in OK, which will keep the severe weather threat south of the area. But expect deep moisture transport over the top of the warm front for a good overrunning and elevated storm event, with skinny CAPE sounding profiles and some elevated instability. So could a few strong storms, with a very small hail threat. The strong moisture transport combined with precipitable water values running 190 to 200 percent of normal, and a coupled upper jet structure favors efficient rainfall, and heavy rainfall potential. So expect periods of moderate to heavy rainfall overnight through early Thu morning. Expect to see widespread rainfall amounts of 1 to 3 inches across the region, with the potential for some areas in extreme SE KS seeing 3 to 5 inches of rainfall. Possible flooding is the main concern. Current location of the flood watch looks right on track, but gonna expand the watch on the northern edge by a few counties, considering rainfall that has already fallen. Expect to see some areal flooding and possible river flooding overnight into early on Thu, especially over the Flint Hills and SE KS. The upper low, becomes vertically stacked early on Thu, which will lead to lingering wrap around clouds/precipitation over the area through Thursday along with cool below normal temperatures. There is some concern for renewed convection along the east-northeast quadrant of this upper low, for the Flint Hills and SE KS for Thu afternoon with clearing from the mid level dry slot allowing good sunshine/destabilization on the edge of deeper moisture plume. The alignment of upper level low/surface low resembles a favorable cold core setup. If this signal is maintained by the models there would be small "window of opportunity" for low topped strong/severe thunderstorms or even some cold core tornadoes in the 0-3km CAPE axis aligned with surface vorticity area. Otherwise, the precipitation will taper off Thursday night as main upper low shifts east into Missouri valley region. Dry weather and near normal temperatures look to be in store for area on Friday. .LONG TERM...(Saturday through Wednesday) Issued at 226 PM CDT Wed May 4 2022 Saturday looks to be a dry weather day with above normal temperatures. Meanwhile, pattern recognition from medium range models are hinting at a very strong 700mb baroclinic zone residing over western Nebraska extending east into northern Kansas Saturday night. This combined with decent upslope of richer moisture in the surface-850mb layer towards western Nebraska looks to spark off convection in the models Saturday evening. This convection would then travel eastward along the 700mb mid-level baroclinic zone in a forward propagating mode, as low level jet veers out leading the convective development. At this time, models are showing this activity possibly clipping central Kansas or remaining north of the area late Saturday night. Something to monitor for any shifts in the models with this signal which could result in severe weather. Otherwise warm and more humid conditions look to prevail for Sunday into Tuesday with richer Gulf of Mexico moisture in place. Some medium range models are showing a frontal boundary pushing southward into this rich moisture which could generate thunderstorms over the region for Tuesday afternoon or Tue night. Ketcham && .AVIATION...(For the 00Z TAFS through 00Z Thursday evening) Issued at 651 PM CDT Wed May 4 2022 Widespread MVFR and IFR this evening may transitions to predominately IFR and LIFR as we move through the overnight hours with multiple rounds of showers and storms bringing heavy rainfall to much of south central and southeast Kansas. East and northeast winds will keep abundant boundary layer moisture in place so locations that are not raining may see more LIFR with low cigs while conditions improve to IFR under the showers and storms although visibilities may keep LIFR the predominate flight category through much of the night and into the morning hours on Thu. A cold front will eventually arrive across the area on Thu ushering in northwest winds and some drier air which may help to mix low cigs out from west to east late in the day tomorrow. && .HYDROLOGY... Issued at 226 PM CDT Wed May 4 2022 Flood watch has been expanded a few more counties to the north, given rainfall that has already occurred. Scattered showers and storms will continue late this afternoon and become more widespread late this evening into tonight. Widespread 1 to 3 inches of rainfall is expected with a few locations in southeast Kansas having potential to see amounts greater than 3 inches. This will result in rises on rivers and streams with some minor flooding problems in low lying areas. Ketcham && .PRELIMINARY POINT TEMPS/POPS... Wichita-KICT 55 64 50 73 / 80 60 40 0 Hutchinson 52 60 47 73 / 90 60 30 0 Newton 54 62 49 72 / 90 70 40 0 ElDorado 56 64 51 71 / 90 70 50 0 Winfield-KWLD 57 66 50 73 / 90 60 30 0 Russell 47 55 44 75 / 90 70 30 0 Great Bend 48 55 43 75 / 90 60 20 0 Salina 51 59 48 72 / 90 70 40 0 McPherson 52 59 47 72 / 90 70 40 0 Coffeyville 58 70 52 72 / 100 70 50 0 Chanute 56 70 53 70 / 100 80 60 10 Iola 56 71 52 68 / 90 80 70 10 Parsons-KPPF 57 70 52 71 / 100 70 50 0 && .ICT WATCHES/WARNINGS/ADVISORIES... Flood Watch through Thursday afternoon for KSZ070>072-093>096- 098>100. && $$ SHORT TERM...Ketcham LONG TERM...Ketcham AVIATION...MWM HYDROLOGY...Ketcham
Area Forecast Discussion
National Weather Service Indianapolis IN
1003 PM EDT Wed May 4 2022 .Forecast Update... Issued at 1003 PM EDT Wed May 4 2022 The forecast remains in good shape. Clouds have persisted across Central Indiana as low level moisture remains in place. These clouds may break up a bit overnight in some locations. Unfortunately, clouds will increase yet again Thursday morning ahead of an approaching warm front. Hi-res models show precipitation may move in quicker than expected tomorrow. No changes were made to POPs at this time. If this trend continues then adjustments to POPs will be warranted. && .Short Term...(This evening through Thursday night) Issued at 239 PM EDT Wed May 4 2022 A veil of clouds continues block the light across Central Indiana this afternoon. High Pressure was found over the Great Lakes while another high was found across the northern Gulf of Mexico. A cold front was found in between these systems...stretching across Appalachia toward northern AL and MS. Clouds persisted in the wake of the front across the Ohio valley along with cool northerly flow from the high to the north. Water Vapor imagery shows weak ridging in place over Indiana. A disturbance in the weather was found over Colorado...allowing for diffluent flow aloft over the plains as moisture was streaming northeast. Tonight... The upper level weather disturbance over Colorado is expected to push east...allowing for a continue SW flow aloft to advect eastward into the Ohio Valley. Meanwhile at the surface...high pressure over the Great Lakes will continue to push east...but continue to provide NE surface flow to Central Indiana. This will be an ideal setup for overrunning tonight. Time heights show subsidence within the lower levels tonight with lift aloft along with saturated lower levels. Forecast soundings also show the classic overrunning wind profile with east winds at the surface and westerly winds aloft. Thus will trend toward a mostly cloudy sky tonight. Given the clouds and weak warm air advection...will trend highs at or above the NBM...which should be in the upper 40s to around 50. Thursday and Thursday Night... Surface low pressure is expected to develop over the SW plains and deepen. As this occurs it will begin to move east with the associated disturbance aloft. The surface flow will begin to interact with the stalled remains of the frontal boundary to the south and begin to move that front back north as a warm front. Diffluent SW flow looks to be in place aloft ahead of the low on Thursday and Thursday Night. Forecast soundings and time heights show deep saturation arriving across Central Indiana on Thursday afternoon as pwats surge over 1.36 and strong lift is depicted. This saturation looks to to be best on late Thursday afternoon and again on late Thursday night. The GFS 305K isentropic surface shows strong upglide on Thursday afternoon and late on Thursday night with pwats over 5 g/kg. HRRR has trended toward a shield of precipitation pushing east into Central Indiana on Thursday afternoon. Thus will aim for dry weather in the morning...but trend pops toward categorical at or shortly after 18Z as the first wave of forcing arrives. Will once again carry high pops on Thursday night...with highest values during the overnight hours when forcing is again best. && .Long Term...(Friday through Wednesday) Issued at 239 PM EDT Wed May 4 2022 Quite the pattern change expected to take place in the long term as cool and wet conditions this weekend transition to hot, humid, summer-like weather next week. Friday - Saturday Nearly stacked area of low pressure in the Central Plains slowly moves eastward along an E-W oriented boundary stretched across the Ohio Valley. GFS and EC ensembles still show some spread regarding the exact track as it moves through Indiana. Larger spread with the ECE members with the low potentially tracking anywhere from the Ohio River to the Michigan border; while the GFS ensembles are clustered in Southern Indiana and right along the Ohio River. NBM currently splits the difference with the surface low tracking right along the I-70 corridor. While the overall track will have influence on where the axis of heaviest rain sets up, surface temperatures, and thunder potential; confidence is high in below normal temperatures and widespread rainfall for Central Indiana on Friday. Current thinking is that rain and elevated thunderstorms along a warm front will be ongoing Friday morning. As the surface low moves directly over the region, expect light rain and potentially thunderstorms to continue through the day. While thunder is in the forecast across all of Central Indiana, best chance for thunder and stronger storms remains across South Central Indiana closer to the warm sector where slightly higher instability exists. Still will have to monitor the track of the low as a further north track could bring the potential for strong to severe storms further northward into Central Indiana. Given the slow nature of this system, there is a marginal to slight risk of flooding across much of the state as 1 to 2 inches of rain could fall on already saturated grounds. The low slowly departs to the east on Saturday while high pressure settles over the region. With abundant low level moisture in the PBL and high pressure moving in, expect low stratus and possible drizzle to linger through the day. Expect ceilings to rise during the day; however with subsidence aloft trapping moisture near the surface and little to no forcing, clouds will be stubborn to clear out. As for temperatures, expect a 5 to 10+ degree gradient from north to south across the area. Confidence is lower with the temperature forecast as a track farther north (south) will lead to warmer (cooler) surface temperatures. For now, keeping low to mid 60s across north Central Indiana and low to mid 70s across South Central Indiana. Sunday - Next Week Beginning Sunday and persisting through next week, a major pattern change takes place across much of the eastern half of the CONUS as ridging builds in and a surface high parks itself across the Northeast. Many forecast signals are pointing towards a summer-like pattern developing and persisting increasing forecast confidence in the long term. Cluster analysis reveals strong agreement among models in a highly amplified ridge over the Great Lakes and Northeast early to mid week. NAEFS and ENS are indicating 30+ year climatological maximums in 850 mb temperatures and high moisture content/humidity levels. Flow turns southerly on Sunday and increases through early next week advecting in a much warmer and humid airmass. Temperatures aloft dramatically increase to 16 to 20C at 850mb by midweek. With a well mixed atmosphere, expect very steep low level lapse rates mixing down the anomalously warm air aloft to the surface. Highs in the 80s expected Monday through at least midweek. Would not be surprised for a few sites to reach their first 90 degree day of the year sometime next week as EC ESAT tables show low to mid level temperatures 2 to 3 standard deviations above normal. With all this in mind, went above NBM guidance for temperatures next week. On top of the summer- like heat, oppressive mid-summer like humidity values will surge northward as moist tropical air flows northward from the Gulf of Mexico. Dew points could potentially reach the lower 70s at times next week leading to heat indices well into the 90s. By mid to late next week, guidance indicates a broad upper low retrograding westward from the Atlantic to the Southeast CONUS. With the potential for lower pressure moving into a very unstable, warm, and humid airmass, will have to watch the potential for thunderstorms once again by the end of next week. Confidence is low regarding any details past midweek as long term guidance tends to struggle with the break down of blocking patterns. && .Aviation...(00Z TAF Issuance) Issued at 749 PM EDT Wed May 4 2022 IMPACTS: - VFR cigs through daybreak tomorrow, MVFR cigs developing by 16Z Thursday DISCUSSION: High pressure in place across the Great Lakes will continue to provide a cold NE surface flow across the Central Indiana TAF`s through the early morning hours. NE winds at 5-10kts will shift to E by 07z tomorrow morning. All TAF sites are in VFR conditions except KHUF. Expect ceilings to improve through the night with VFR conditions across Central Indiana over the next few hours. A warm front is expected to approach Central Indiana from the Plains tomorrow and will increase rain chances Thursday afternoon. Thus light rain showers were added in the late parts of the TAFs. Ceilings will drop to MVFR by 16z Thursday due to the approaching warm front. && .IND WATCHES/WARNINGS/ADVISORIES... None. && $$ Update...Melo Short Term...Puma Long Term...CM Aviation...Melo
Area Forecast Discussion
National Weather Service Norman OK
638 PM CDT Wed May 4 2022 ...New AVIATION... .MESOSCALE UPDATE FOR Severe Thunderstorm Threat... Issued at 1226 PM CDT Wed May 4 2022 Regional satellite/radar show convective trends increasing over western/southwestern Oklahoma. A complex warm front structure exists with convective reinforcement/outflow, but the effective front appears to be oriented from roughly Harmon County to McClain County... to north of Ada. Three hour temperature changes are now pushing 15 degrees along the Red River as warm/moist air advection is well underway. Visible satellite imagery shows gradually increasing vertical development of cumulus fields over north Texas, and a transition to stable wave clouds over southwestern Oklahoma...indicative of low level shear. All of these current trends suggest an increasing threat of elevated hailstorms north of the progressing warm front within the next 1-3 hours. This risk of surface based convection will increase notably as the boundary layer recovers along/south of the warm front over southern-central Oklahoma by/after 3 PM. All hazards would be possible with any discrete supercells that can form in this environment. Convection allowing models continue to show a strong signal for additional organized severe convection to approach southwestern Oklahoma and western north Texas by 00z, again with all severe weather hazards possible. This activity expected to grow upscale into a linear complex as it approaches central Oklahoma later this evening. Heavy rainfall and flash flooding will become an increasing danger as this subsequent round of convection progresses across the area. && .SHORT TERM... (This evening through Thursday) Issued at 324 PM CDT Wed May 4 2022 The atmosphere remains primed with abundant moisture and moderate to strong instability for numerous storms including supercells to develop through tonight. Much of the severe activity will be along and south of an advancing warm front currently stretched across the Red River where lower 70s dewpoints are in place. Latest RAP has a good handle on the warm front, lifting it into southern Oklahoma to stretched just south of the I-40 corridor by early evening. As a result, the highest risk for severe storms will be along and south of I-40, with all hazards possible including hail up to baseball size, while DCAPE values will support severe downburst gusts and deep-layer shear will be sufficient for tornado development with some of these supercells. The tornado risk will increase even more this evening across southwest Oklahoma and western north Texas where a low-level jet will start up increasing the low-level shear. Also by evening, outflow boundaries from earlier storms could also reinitiate storms. Heavy rainfall with these storms will also result in risk of flash flooding and river flooding. A bullseye of near 2-inch column PW values across the eastern half of Oklahoma would be the most likely area for flooding with 2-4 inches storm total accumulations possible. As a result, all of central and southeast Oklahoma will have the highest risk for flooding. A cold front will start digging through tonight with the surface low preceding it. Will continue to see isolated severe storms persist ahead of the front with perhaps a final squall line along the frontal boundary. && .LONG TERM... (Thursday night through next Tuesday) Issued at 324 PM CDT Wed May 4 2022 By Thursday evening into Friday, expecting the upper low over northern Oklahoma & Kansas to be exiting the Central Plains into the Midwest region as our upper flow transitions into a ridge pattern, while high pressure starts building in down at the surface. The ridging should keep us dry through Monday with a warming trend. Although temperatures should be nearly seasonably average for early May on Friday, a return of gusty south winds on Saturday will raise temperatures well above average, to downright hot across our west well into the 90s with a few of our western north Texas counties approaching triple digits. Our "hot" trend will continue Sunday and Monday with all of western north Texas and adjacent Oklahoma counties with triple digit highs and well in the 90s across the remainder of our Oklahoma counties. Overall, MaxT`s on Sunday & Monday could be as much as 20 degrees warmer than climatically average for early May afternoons. South winds on Saturday will also bring a return of gulf moisture transport up through the Southern Plains forming a dryline across the Texas/Oklahoma Panhandles, while models suggest the dryline advancing further across westcentral Oklahoma by Sunday afternoon with models keeping it stretched across western Oklahoma through Monday. However, NBM keeps the dryline entirely across far western Oklahoma, so some uncertainties with the dryline position on Sunday. Will see at least 60s dewpoints east of the dryline, although both GFS & ECMWF are projecting higher to near 70 degrees, so need to watch that trend. Increasing muggy air and lots of instability east of the dryline with Saturday looking strongly capped. However, will need to keep an eye on a weaker cap Sunday due to diurnal afternoon heating, but due to uncertainties at this time will not introduce any storm POPs. The return of south winds will also bring a return of a strong southerly low-level jet each night, so we will see windy conditions increasing each day with Monday possibly reaching wind advisory criteria. With a dryline across our west by Sunday and gusty winds may also increase fire weather conditions across our west on Sunday & Monday afternoons. However, fire weather will be conditional based on how much rainfall accumulated across our west during the short term of the forecast. By Monday we also get into a southwest flow aloft pattern as a large amplitude trough starts digging across the western half of the country. Could see a short-wave propagate through the trough on Tuesday with low storm POPs across our area. Did go higher with the windspeeds this weekend through early next week using the NBM 90th percentile in the wind grids. && .AVIATION... (00Z TAFS) Issued at 633 PM CDT Wed May 4 2022 Ongoing showers and thunderstorms will continue to spread across much of the forecast area through the evening and overnight. Large hail will be a threat with the stronger storms, especially along the warm front (stretching approximately from central Oklahoma down through southwest Oklahoma). Meanwhile MVFR to IFR ceilings and patchy fog will persist through the night. A cold front will move through late tonight, bringing north winds and sweeping convection off to the east. Day && .PRELIMINARY POINT TEMPS/POPS... Oklahoma City OK 60 71 49 77 / 90 40 0 0 Hobart OK 56 74 46 82 / 80 30 0 0 Wichita Falls TX 61 79 51 85 / 70 30 0 0 Gage OK 48 66 42 83 / 80 30 0 0 Ponca City OK 58 69 49 74 / 100 50 10 0 Durant OK 64 79 53 82 / 90 80 10 0 && .OUN WATCHES/WARNINGS/ADVISORIES... OK...Flood Watch through Thursday morning for OKZ006>008-011>013- 017>020-023>032-037>048-050>052. TX...Flood Watch through Thursday morning for TXZ086-090. && $$ SHORT TERM...68 LONG TERM....68 AVIATION...14