Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 06/25/22

Area Forecast Discussion...UPDATED
National Weather Service Aberdeen SD
941 PM CDT Fri Jun 24 2022 .UPDATE... Issued at 939 PM CDT Fri Jun 24 2022 Storms continue across much of the western half of the CWA, but appear to beginning to lose strength as time goes on. No major changes made to the forecast at this time. && .SHORT TERM...(This Evening through Saturday Night) Issued at 256 PM CDT Fri Jun 24 2022 The SPC has most of the CWA in an enhanced risk of severe storms. Showers and thunderstorms are likely this evening moving west to east as a surface trough moves off the Rockies to combine with a cold front. Confidence is low on exactly when and where storms will form as high resolution models struggle with initiation timing. However, the HRRR seems to be in line with current radar trends. Bulk shear values are relatively unimpressive early at around 30kts, but after the front moves through they ramp up to around 50kts. MUCAPE values range from 3000 to 5000 J/kg in eastern counties which is also the area of higher moisture. CIN values are between -50 and -150 J/kg. This could hinder, but not prevent, convective formation. However, this cap will continue to erode as the front moves east. The focus will be western portions of the CWA where the cap is less and the cold front intersecting with the surface trough from the Rockies will provide lift. All threats are possible with these storms. Saturday is expected to be significantly cooler than the last few days as a result of decreasing heights with the trough moving in. Temperatures at 850 mb decrease from 22C to between 8 and 10C. These temperatures will mix down to the surface as CAA generates some gusts between 35 and 45 mph in central and western SD. Corson and Dewey counties may need a Wind Advisory. .LONG TERM...(Sunday through Friday) Issued at 256 PM CDT Fri Jun 24 2022 The long term period will feature a state of flux in the upper- levels, which will translate to a variety of weather conditions at the surface. Initially, at 12z on Sunday, a strong, stacked low/upper low pressure system will be across the southern Hudson Bay in Canada. With strong high pressure simultaneously across the Northern Rockies, a relatively tight pressure gradient will be in place across the High Plains, leading to breezy northwest winds. While the low shifts further east through the day, bringing stronger winds aloft along with it, daytime heating and mixing should lead to continued breezy conditions through the day, especially across the eastern CWA. Sunday`s airmass will remain relatively cool and dry, under the influence of that northerly flow, with high temperatures generally in the mid to upper 70s and dewpoints in the mid to upper 40s. Northwest upper-level flow remains in place through Tuesday, but southerly return-flow will have developed, leading to increased warmth (especially across central SD) and a gradual increase in humidity. Shortwave energy brings the best chance for precipitation across North Dakota and northern Minnesota Monday night, but this cannot be ruled out across the northeastern CWA as well. An upper- level ridge builds in temporarily Tuesday night into Wednesday, which would translate into the warmest day of the week with highs in the 90s (though there is also more spread in potential outcomes among the models on this day than any other - the majority of ECMWF ensemble members position the upper-ridge further west - so confidence is low on details). Showers and thunderstorms are possible Wednesday evening and night, as shortwave energy quickly flattens the ridge. Models are in better agreement then about developing generally westerly flow aloft to end the week, with slightly cooler temperatures and occasional additional chances for showers and thunderstorms whenever forcing works through the region. && .AVIATION...(For the 00Z TAFS through 00Z Saturday Evening) Issued at 636 PM CDT Fri Jun 24 2022 Terminals KABR,KATY,KPIR,KMBG A cold front crossing the region this evening will bring showers and thunderstorms to all terminals. The thunderstorms will bring MVFR and possible IFR conditions. Winds will become breezy from the northwest behind the passage of the cold front. && .ABR WATCHES/WARNINGS/ADVISORIES... SD...None. MN...None. && $$ UPDATE...Parkin SHORT TERM...KK LONG TERM...Lueck AVIATION...SD
Area Forecast Discussion
National Weather Service Dodge City KS
617 PM CDT Fri Jun 24 2022 ...Updated Aviation Discussion... .SHORT TERM...(This evening through Saturday) Issued at 124 PM CDT Fri Jun 24 2022 The early afternoon RAP analysis and water vapor loop revealed a synoptic scale setup characterized by a broad, rather flat ridge axis in the mid/upper troposphere centered across the Midwest. A low amplitude trough was pushing east across the Northern/Central Rockies, and water vapor imagery suggests at least a little bit of North American Monsoon circulation advancing northeastward from New Mew Mexico into central/eastern Colorado. The surface analysis showed a weak surface low across west central Kansas with a plume of hot air advancing northeast across southwest Kansas, where DDC, LBL and surrounding stations were already at or slightly below 100F prior to 18Z. In the forecast for tonight, we will carry some Slight Chance POPs across west central KS, east of the mentioned weak surface low as well as some Slight Chance POPs across far southwest Kansas. Neither region will likely see much in the way of organized thunderstorm activity given the rather dry low levels in place with dewpoints mainly in the mid to upper 50s up north...and upper 40s to lower 50s in the southwest. Early Saturday morning, a strong cold front will push south as the aforemtioned upper level trough moves out across the Northern Plains. There will be anomalously chilly air behind this front with 850mb temperatures as low as the +7 to +10C range across western Nebraska early Saturday morning. The 850mb temperatures will modify due to mixing later on in the day Saturday, but the cold advection behind the front will nevertheless have an impact in temperatures on Saturday. We will likely see midday or early afternoon highs in the mid to upper 80s before temperatures plateau or only very slowly rise through early evening. The majority of models suggest that some small component of the North American Monsoon circulation with deeper moisture will push back southeast into southwest Kansas, which may result in scattered showers/thunderstorm in the afternoon poleward of the surface cold front across southwest Kansas. There is a much better chance for more organized strong/marginally severe convection along the front itself, but by late afternoon the front will be positioned across western Oklahoma and the Texas Panhandle. Later Saturday evening and night, however, there will be a much better chance for more organized showers and storms poleward of the front from northeastern New Mexico into southwest Kansas...particularly far southwest Kansas. The north-south position of greatest 12-hr model QPF has shifted south just a little bit for the 00-12Z Sunday period, so the highest Likely POPs will be confined to areas now south of the Arkansas River (especially from Elkhart to Liberal and points east-northeast toward Coldwater-Pratt- Medicine Lodge. It is beginning to look more and more like areas along/north of K-96 may not see much rainfall at all during this 12- hour Saturday Night period. .LONG TERM...(Saturday night through Friday) Issued at 124 PM CDT Fri Jun 24 2022 Western Kansas will be under the influence of a very cool, polar surface high the beginning of this Long Term Period (Sunday and Monday) with afternoon temperatures most likely remaining in the 60s to lower 70s across much of the southwest Kansas region. The main question in the forecast will be how much additional rainfall will occur. It is a complicated forecast for precipitation, because the best low level frontogenesis will be well to the south of Southwest Kansas Sunday and Monday. Yet, the combination of a right-entrance region of the polar jet in vicinity of southwest Kansas in tandem with the continued, at least minor, infusion of the North American Monsoon circulation and its deep tropospheric moisture, will support organized shower and thunderstorm activity well north of the polar front -- especially across far southwest Kansas closer to the Raton/Black Mesa region. Precipitation chances will really wane by Tuesday, though, as the jet streak weakens and pulls away from the Central Plains with an upper level ridge building across the Four Corners region. The anomalously cool airmass will modify quickly Tuesday and Wednesday, such that by Thursday, we will likely be right back to our typical upper 90s/near 100 degrees for afternoon temperatures. We could be entering another potential wet period end of next week toward the following weekend (centered around 1-3 July time frame) as the consensus among the global spectral models is that the summer subtropical high will not be all that expansive and will likely be oriented more east-west without much of an amplified ridge. This is favorable for MCS activity across the Central Plains region. && .AVIATION...(For the 00Z TAFS through 00Z Saturday evening) Issued at 559 PM CDT Fri Jun 24 2022 A few isolated thunderstorms will be possible over the next few hours in the Hays area and north of Garden City. Elsewhere a period of ceilings in the 7000 to 12000ft AGL are expected early this evening. Gusty west to southwest winds will decrease after sunset. This will be followed by an increase in winds to 40 to 45 knots near 2000ft AGL level early tonight across portions of southwest Kansas. Also overnight a surface cold front will cross southwest Kansas between 03z and 12z Saturday and as this surface boundary passes the west to southwest winds will shift to the north and increase into the 15 to 20 knot range. && .PRELIMINARY POINT TEMPS/POPS... DDC 72 88 60 71 / 10 20 60 30 GCK 69 85 58 71 / 10 20 50 30 EHA 68 86 58 66 / 20 30 70 60 LBL 69 89 59 70 / 20 20 70 40 HYS 71 84 60 74 / 10 20 30 20 P28 74 95 64 75 / 10 20 60 20 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Umscheid LONG TERM...Umscheid AVIATION...Burgert
National Weather Service Hastings NE
727 PM CDT Fri Jun 24 2022 ...Short Term and Aviation Update... .UPDATE... Issued at 726 PM CDT Fri Jun 24 2022 Some of our latest thoughts regarding thunderstorm/severe storm trends: - Thus far, strong capping (evidenced by 700 millibar temps in the 12-14C range) has held any "true" afternoon convection at bay (other than a few showers/very weak storms earlier mainly east of Hwy 281 in Nebraska). Even the attempts at high-based storms barely south-southwest of our CWA (Hays KS area) have struggled mightily). - As fairly well captured by higher-res models (CAMS) such as 18Z NAMNest/22Z HRRR, the main "action" at this time is still well to our west over western NE up into SD along the greater low level convergence along a north-south oriented surface trough. - So, the million dollar question: what are WE in for tonight? Well, to be perfectly honest and reiterate/build upon the excellent previous afternoon discussion below...there are still some question marks. Putting as much faith in the CAMS as we dare, odds are fairly good that our entire CWA should largely remain storm-free through around 10 PM. - However, anytime beyond (roughly) 10 PM and lasting until (roughly) 2-3 AM we begin a window of opportunity for POSSIBLE severe storms, which if were to occur would primarily be a function of storms to our west merging into at least a broken (if not more solid) line, developing a decent cold pool and charging eastward into our CWA. This would mainly foster a wind threat, although any embedded supercell structure would perhaps foster a large hail threat as well. It`s possible some more isolated activity or a separate storm complex could try going up ahead of anything moving in from the west, but given such warm air aloft overhead and also the nose of the low level jet aiming more into northeast NE versus our area, this possibility would appear more favored over the OAX CWA. - IN SUMMARY: It "appears" that strong capping will most likely "save" us from any true isolated daylight severe storm threat, but especially the 10PM-3AM time frame bears close watching for a possible severe storm threat in our CWA. As mentioned in the main discussion below however, nothing appears to be a "sure thing" tonight and we`ll continue to closely monitor things as they evolve. && .DISCUSSION...(This evening through Friday) Issued at 415 PM CDT Fri Jun 24 2022 Main forecast concerns are chances for strong/severe thunderstorms within the next 12 hours. Summary: Tricky thunderstorm forecast in the short term has several ingredients are in place for severe weather, but not all. This results in a highly conditional and generally uncertain forecast in the first 12 hours, or so. Generally speaking, an isolated strong to severe thunderstorm could develop from the Tri-Cities north and east at any time this afternoon and evening...but the "best" chances for thunderstorms and severe weather will probably hold off until after sunset when a line of thunderstorms MAY move in from the west. Even this scenario, however, is uncertain as a layer of warm air aloft (capping) could prevent most thunderstorm activity, or at least the really strong stuff. A cold front will move through the area Saturday AM and bring us refreshing, breezy NW winds, drier air, and cooler temperatures for the weekend. Temperatures will steadily warm through next week, likely culminating with at least near-triple digit heat in about a week. Early indications are for cooler, but potentially active, pattern for the 4th of July weekend. Forecast Details: Low confidence forecast through tonight due to mixed hi-res guidance, somewhat messy sfc/mid level pattern, and warm mid level temperatures amidst weak forcing. Starting off aloft...area remains in "dirty" SW upper flow with obvious connection to a monsoonal moisture plume. A weakening, positively tilted shortwave trough stretches from W Dakotas SW to the Four Corners, with another stronger trough nosing S into MT. Appears the primary upper forcing will remain across the N Plains, but much like yesterday, at least one or two weak perturbations are likely to work through the area through tonight. These waves could be strong enough to support convection as early as this aftn/ we`re currently seeing from Doniphan to York...but capping in the H8 to H7 layer (as evident by 12-14C temps at H7 per latest SPC mesoanalysis) may very well be strong enough to prevent sfc-based activity altogether. However, IF a storm can breach the cap and become sfc based, the aftn/eve environment would support strong- severe convection with strong instability (MLCAPE 2-3K+ J/kg) and modest shear (0-6km bulk shear 25-30kt, supported by significant veering in lowest 3km) in place. Dew points in the low 70s amidst backed low level flow could, in theory, also produce an iso tornado. Again though, the eve tstm potential is VERY conditional and more than likely not going to pan out. Somewhat more likely, though still conditional and uncertain, is that convection develops and organizes along sfc trough over W Neb., then gradually shifts E this eve and overnight. The degree to which this activity can make it into our CWA will likely depend on cold pool development to our W this eve. IF a strong cold pool develops, then this activity will likely have a significant reservoir of strong MUCAPE to work with with temps in the 80s and dew points in the 70s. This scenario would be similar to earlier runs of HRRR and 12Z/18Z runs of NAMNest. However, if activity fails to organize a strong cold pool, then diurnal cooling and aforementioned warm mid level temps could prevent activity from even making it into the area altogether...similar to recent runs of the HRRR. So as mentioned above, run to run and model to model consistency amongst the hi-res guidance is lacking and contributing to low confidence. The main severe threat overnight would probably be damaging wind gusts if a line does indeed form, but large hail will also be possible, esp. with any convection that remains more cellular. The actual cold front will enter NW portions of the CWA around sunrise and quickly progress SE through the morning. The primary instability axis should set up S/SE of the area by Sat aftn, but at least minor elevated instability may persist further N along the elevated frontal slope that could support some iso to scat weak convection roughly along and S of the NE/KS state line through mid to late aftn. Severe weather is not expected on Sat in our area. NW winds will be pretty brzy immediately along and behind the front, with gusts 30-35 MPH possible for esp. south central Nebraska. The brzy NW winds will usher much drier, more comfortable air into the region, as well as cooler air. Highs on Sat will range from near 80F north, to mid 80s S, but lows Sat night will fall well into the 50s, for most, and perhaps even upper 40s far N/W. Sun looks to be the coolest of this forecast with highs only in the 70s, and lows Sun night again in the 50s. Mild, dry conditions, light winds, and plentiful sunshine should make Sun a very pleasant day for those looking for a break from hot/humid, and even Mon will be fairly nice, though a bit warmer. Temps become notably warmer on Tue with most areas returning to the 90s, before even hotter temps in the upper 90s to low 100s move in for Wed-Thu as upper ridging at least briefly amplifies over the central/southern Rockies and Plains. Early indications are that the ridge will break down and upper flow will turn zonal, or even NWrly, atop a stalling front in the low-levels somewhere over the Central Plains. Where exactly the front stalls out remains uncertain, but there`s a chance it could be over or very close to the forecast area, which would result in cooler and fairly active conditions for the 4th of July holiday weekend. && .AVIATION...(For the 00Z KGRI/KEAR TAFS through 00Z Sunday) Issued at 726 PM CDT Fri Jun 24 2022 General overview: A tricky TAF period with regard to several elements including: thunderstorm potential (maybe severe?), timing of wind shifts and also possible low ceilings. Overall though, the majority of the period should prevail VFR ceiling/visibility and be precipitation- free. Read on for more element-by-element details. Thunderstorm potential: Although we are drawing closer to POSSIBLE thunderstorms, there is still some decent uncertainty in how things evolve. Do not have the confidence for any TEMPO groups yet (let alone prevailing thunder), but have confined a generic "vicinity thunderstorm" (VCTS) mention to what appears to be the most favored 4-hour time frames (04-08Z KEAR/06-10Z KGRI). IF storms roll in during this time, they could be severe, with gusts around 50KT being the main threat, along with brief heavy rain and a lesser threat of large hail. Cannot rule out at least a few showers/weaker storms beyond these most favored times, but the VCTS period should capture the main time frame of concern. Ceiling/visibility: Although confidence is very high in VFR for these first several hours this evening and also late in the period Saturday afternoon, the early morning through late morning hours are a big question mark, as at least a few sets of usually-reliable guidance are strongly suggesting perhaps several hours of MVFR ceiling (with brief IFR not out of the question). However, convection sometimes has a way of "messing up" low cloud forecasts this time of year, so opted against buying in to low ceilings wholesale just yet. However, did introduce prevailing MVFR ceiling for anywhere from 3-7 hours on Saturday morning. Stay tuned for plenty of adjustments here in later forecasts (possibly significant?). Winds: Compared to other TAF elements, this one carries higher confidence (at least outside of thunderstorm influences). Not accounting for any possible thunderstorm-enhanced outflow, these first several hours will feature fairly fairly light breezes, gradually shifting from east-southeasterly to north-northeasterly. Although passing storms could subsequently result in a period of highly variable direction/speed, a fairly strong cold front by summer standards will push through around sunrise, solidly switching winds to northerly through the entire latter half of the period (Saturday daytime). Sustained speeds will commonly average up to around 20KT/gusts 25-30KT before speeds start to slacken late afternoon. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ UPDATE...Pfannkuch DISCUSSION...Thies AVIATION...Pfannkuch
Area Forecast Discussion
National Weather Service Grand Junction CO
631 PM MDT Fri Jun 24 2022 .UPDATE... Issued at 630 PM MDT Fri Jun 24 2022 Greatly improving conditions this evening looking at sat and observations has allowed the Grizzly Creek Watch to be taken down. At the moment do not see any other issues as the more humid air vacates to the East. Will adjust most pops down and update the sky grids to reflect current conditions. && .SHORT TERM...(Tonight through Saturday night) Issued at 339 PM MDT Fri Jun 24 2022 Showers and thunderstorms developed this morning as the mid-level trough discussed over the past several days began to track eastward across Utah. Satellite and RAP 500 mb analysis indicated the trough extended roughly along a KRWL to KCNY line 21Z. Storms continued to fire along and ahead of the trough where mid-level lift was maximized in the unstable airmass. As the previous shift pointed out, decent shear (30 to 40 kts) and CAPE values in excess of 1,000 J/kg suggest the potential for some organized storms. The main threat from the strongest cells is strong outflow wind gusts, though hail from 1/2 to 3/4 inches is also possible. In addition, the burn scar at Grizzly Creek is susceptible to rain rates of 0.60"/hour which have already been recorded with some storms. Therefore, the Flash Flood Watch will continue for Glenwood Canyon. Models were in good agreement with the progression of the trough and all indicated its axis will shift east of the Continental Divide by 00Z/Sat. Subsidence, advection of drier air and the stabilizing influence of diurnal cooling will bring an end to moist convection by midnight with clearing spreading west to east this evening. Precipitable water values decrease for Saturday falling to near 0.50" on average across the area. Reduced moisture across the region will lead to less widespread showers and thunderstorms with activity expected to be contained along the Continental Divide with the San Juan Mountains favored. Moist convection ends for most locations Saturday in response to diurnal cooling. However, nocturnal showers may continue over the southern San Juan Mountains and the Durango to Pagosa Springs corridor where moisture begins to deepen once again. Overnight lows will hover near normal while highs on Saturday climb by about 5 degrees for most locations in response to increased sunshine. .LONG TERM...(Sunday through Friday) Issued at 339 PM MDT Fri Jun 24 2022 Sunday is still looking like the most active day for the early week period as a ridge builds in over the Great Basin and the high over the Southern Plains drives a stream of moisture north into the Four Corners region. PWAT values of 0.6 to 0.8 inches are on tap for the day, plenty of juice to allow for widespread showers and thunderstorms to form off the higher terrain. Those above normal PWAT values also mean the threat of heavy rainfall remains. By Monday, the high over the Great Basin begins to shift east in response to a deep low off the Pacific Northwest. This drives a drier northwesterly flow over eastern Utah and western Colorado, cutting the tropical moisture plume at the southern border of Utah and Colorado. That said, forecast PWAT values are right around normal for this time of year, and there should be enough moisture still pooled over the area for afternoon convection to trigger once again that afternoon, though with less coverage compared to the day before. Tuesday looks to be the "driest" day of the period, though the word "dry" is maybe a bit misleading. The ridge axis will be moving overhead, and forecast PWATs will be at or maybe even slightly below average for the day, so convection will be at its most limited of the period. Still expect some widely scattered showers and storms to fire off the higher terrain through the afternoon, however. By Wednesday that low off the Pacific Northwest moves onshore along the Canadian border. While the Four Corners won`t see any direct effects from it, the influence of this area of low pressure extends south along the West Coast and helps to nudge the Southern Plains high further southeast. Under these conditions, the monsoonal moisture tap turns on once more, with PWATs climbing back up to 150- 170% of normal by Wednesday night. With the increased moisture, shower and storm coverage will once again be on the increase for the end of the week. Long range models even hint that these conditions will remain into the weekend. Temperatures are expected to continue near normal through the period. && .AVIATION...(For the 00Z TAFS through 00Z Saturday evening) Issued at 532 PM MDT Fri Jun 24 2022 Much of the thunderstorm activity is decreasing early this evening and this trend should continue through sunset. The threat of gusty outflow winds or lightning appears to be limited to the KASE TAF early in the forecast. Otherwise VFR conditions can be expected through the next 24 hours. && .GJT WATCHES/WARNINGS/ADVISORIES... CO...None. UT...None. && $$ UPDATE...15 SHORT TERM...NL LONG TERM...BGB AVIATION...TGJT
Area Forecast Discussion
National Weather Service Huntsville AL
826 PM CDT Fri Jun 24 2022 ...New NEAR TERM... .NEAR TERM... (Tonight) Issued at 826 PM CDT Fri Jun 24 2022 Around a 10 degree dewpoint gradient across the Tennessee Valley this evening. Dewpoints are in the low 70s across northeast Alabama and southern Middle Tennessee to the low 60s in portions of northwest Alabama. There are a few light showers across northeast Alabama with this deeper moisture but they have diminished in coverage and intensity recently with the loss of daytime heating. The latest HRRR indicates at least some chance for a few isolated showers near the Alabama/Georgia state-line during the overnight hours. The moisture decreases rather quickly to the west with PW values below 1.5 inches forecast overnight to the west of I-65. Overall, kept at least some mention of precipitation in the forecast throughout the overnight hours along the Alabama/Georgia state-line. Lows will be on the milder side tonight with lows in the upper 60s to mid 70s. && .SHORT TERM... (Saturday through Monday) Issued at 253 PM CDT Fri Jun 24 2022 The upper level ridging that has prolonged the ongoing heat wave will continue and intensify heading into this weekend with 500 mb heights reaching 591+ dm. Persistent troughing off the East Coast will gradually extend into portions of northeast AL. As a result, high temperatures will see a gradient with only mid to upper 80s in the northeast and peaking in the mid to upper 90s for northwest Alabama this weekend. Onshore flow will cause dew points to surge into the upper 60s to low 70s, creating a heat index peaking near 100 degrees. A surface convergence axis along the periphery of a surface high pressure system will progress from east to west this weekend, almost as a pseudo-backdoor front. Chances for showers and thunderstorms increase heading into Saturday with 30-45% PoPs east of I-65. The feature to note in the short term period is a shortwave trough that will sweep through the Great Lakes region and push a surface low and attendant cold front through the eastern CONUS Sunday into Monday. This will increase shower and storm coverage by Sunday afternoon and evening with numerous showers and storms on Monday as the cold front pushes through the area. While ample instability is not uncommon for this time of year, which would lead to strong to severe pulse convection, high atmospheric moisture content and the presence of the classic long-skinny CAPE profile will introduce a heavy rainfall threat with potential localized flooding. Otherwise, look for highs to only peak in the low to mid 80s on Monday due to the ongoing convective activity. && .LONG TERM... (Monday night through Thursday) Issued at 253 PM CDT Fri Jun 24 2022 Our long term forecast begins Monday night as the cold front is slowly pushing through the TN Valley with showers and storms covering most of the area. Persistent ridging over the Gulf of Mexico will cause the front to slow down and become the focus for diurnal shower and storm development through the remainder of next week. High temperatures increase from the mid to upper 80s on Tuesday into the low 90s by late next week, which is a much more typical pattern for the beginning of Summer. && .AVIATION... (00Z TAFS) Issued at 609 PM CDT Fri Jun 24 2022 VFR conditions will continue throughout the TAF cycle. A few isolated showers/storms will be possible after 18z at HSV. For now, confidence is too low to include a PROB30 in the TAF. && .HUN WATCHES/WARNINGS/ADVISORIES... AL...None. TN...None. && $$ NEAR TERM...MA SHORT TERM....30 LONG TERM....30 AVIATION...MA
Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
900 PM CDT Fri Jun 24 2022 .UPDATE... Issued at 843 PM CDT Fri Jun 24 2022 Update for severe threat tonight. Numerous storms have developed within a very unstable environment from northwest MN back into central SODAK. The portion of this convection that looks to have the greatest severe potential is the north end of the line segment approaching the Red Lakes. This has developed just on the cool side of the mlCAPE gradient and we expect this line segment to continue following this CAPE gradient toward Duluth, this is where the greatest threat for severe weather will exist tonight. Mesoanalysis also shows a pool of low 70 dewpoints in place over central MN, basically where 6-12 inches of rain fell last night. This pool of higher dewpoints in central MN is out ahead of the line segment approaching Fargo at 9pm. This high degree of low level moisture will likely help sustain a severe risk into central MN, but we`re talking something like 11pm to 2am for the Alexandria to St. Cloud region to have the severe threat. By this point in the night, a decrease in both shear and instability will likely spell the end of the significant severe threat, so although the remnants of this line should make it into the Twin Cities metro around sunrise, it will be on a downward trend and at this time, we do not anticipate needing to extend the watch east, but will obviously monitor that possibility through the night. && .SHORT TERM...(This evening through Saturday night) Issued at 322 PM CDT Fri Jun 24 2022 KEY MESSAGES: - Severe thunderstorms and heavy rainfall possible late this evening through the early morning hours Saturday. - Additional rainfall over the areas hammered with 6-12 inches last night could result in more flash flooding. It`s a tranquil and warm afternoon with fair wx CU, making for a typical summer day. Temperatures have risen to the mid 80s to lower 90s and dew points are creeping up into the upper 60s. A cold front stretches from northeast ND to western SD and will continue eastward tonight. Severe thunderstorms are developing along the front over ND this afternoon in a very unstable environment. As the evening progresses, these storms will encounter a more stable airmass with poor lapse rates and should weaken across western and central MN. Severe storms are still possible in those areas, but they shouldn`t be as numerous as farther northwest. Nonetheless, widespread showers and thunderstorms will advance across central MN overnight. Very heavy rainfall from last night (6 to 12 inches in parts of Morrison, Stearns, and Benton counties) has left the area flooded or saturated. While we aren`t expecting extreme rain totals tonight, any additional rainfall could lead to more flooding. Thus, a Flood Watch has been issued for those locations. Another area of convection is expected to develop over SD or NE later this afternoon near a secondary low pressure center. This low will develop a strong LLJ from the central Plains to IA this evening, increasing moisture transport into MN. This should maintain or strengthen the complex as it tracks eastward into MN overnight. Locally heavy rain will be a concern, but it`s expected to track across an area that is abnormally dry and has missed the bulk of precipitation from the past several events. The two areas of convection will merge late tonight across eastern MN and then exit to the east toward eastern WI Saturday morning. Cooler and drier air will follow Saturday afternoon and Saturday night. .LONG TERM...(Sunday through Friday) Issued at 322 PM CDT Fri Jun 24 2022 KEY MESSAGES: - Cooler/drier conditions Sunday to Monday. - Return of warmer temperatures and moisture by mid-week. - Showers/Thunderstorms possible Tuesday and Thursday. Sunday and Monday The remainder of the weekend appears to briefly cool down as well as dry out. An upper level trough axis will be advancing from west to east across the region with surface high pressure building in from our neighbors to the south. Given the higher pressure aloft will allow for little to no cloud cover except for the patchy stratocumulus fields that you`d typically see on a given summer afternoon. The location of the passing upper level trough, will generate winds to be northeasterly through this period and could become breezy throughout the day Sunday. A shift in the wind direction to Southwesterly will occur Monday night. Temperatures are expected to be below normal on Sunday in the mid-70`s and then reaching the low-80`s Monday. Low`s expected to be in the low to mid- 50`s and slight warmer near 60 in the Twin Cities. Tuesday - Friday As the aforementioned trough fills and departs to our east, the surface high pressure will begin to erode and will allow for a shortwave to advance over our region. Winds will be southwesterly which will allow for some vorticity advection to generate some chances of showers and thunderstorms Tuesday morning for our western counties and then by Tuesday afternoon/evening for our eastern counties. A widespread washout is not anticipated. This shortwave will quickly exit Tuesday night into Wednesday which will briefly build back in high pressure, clear up the skies, and temperatures into the low to mid 80`s for most areas and upper 80`s for Southern MN. On Thursday, our next batch of PoP chances returns as another advancing shortwave moves overhead to our north. Flow will become zonal which will advect a larger batch of positive vorticity and moisture and we should see a greater chance of showers/thunderstorms this day as compared to Tuesday but again a washout is not expected. Friday, skies will clear and under mostly sunny conditions and temperatures near normal for the remainder of the period. && .AVIATION...(For the 00Z TAFS through 00Z Saturday evening) Issued at 643 PM CDT Fri Jun 24 2022 It`s a rather complex forecast for late tonight through Saturday morning, with three bits of forcing all converging on southern MN. First, we have the developing MCS up north of Fargo that will track toward central MN tonight. Second, will be convection forced on the strengthening LLJ over Iowa tonight that will move toward southeast MN. Third is the cold front itself, which looks to move into AXN around 12z, MSP close to noon, and not until near 22z at EAU. Given all of that, we haven`t seen too much with latest guidance to significantly change what we had going in the 18z TAFs, with the main change to delay the arrival of TS by an hour or two at most locations. Biggest concern given the timing for the FROPA is we could have activity linger longer than currently indicated, which the HRRR at least kind of hints at with its scattered forecast reflectivity along the front. Although not a typical time of year for seeing stratus, there is robust model agreement in IFR to low end MVFR cigs moving in with the convection tonight, so confidence is high we`ll see these sorts of reduced cigs, but less confidence on how long they will last. KMSP...MSP is in a tricky spot here as the convection on the LLJ coming out of Iowa looks to stay southeast of MSP. This means we`ll be waiting to see how, or even if we are impacted by a line of storms that will be completely outflow dominate by the time they get this far southeast. Behind the morning convection, the HRRR has been trending a bit more aggressive with activity along the cold front itself, so we`ll have to keep an eye out on the potential for another round of shra/tsra between 16z and 18z. /OUTLOOK FOR KMSP/ Sun...VFR. Wind NW 15G25 kts. Mon...VFR. Wind WSW at 5-10 kts. Tue...VFR. Chc -TSRA. Wind SW bcmg NW 10 kts. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...Flood Watch until 8 AM CDT Saturday for Benton-Isanti-Kanabec-Mille Lacs-Morrison-Sherburne-Stearns-Todd. WI...None. && $$ UPDATE...MPG SHORT TERM...Borghoff LONG TERM...RMD AVIATION...MPG
Area Forecast Discussion
National Weather Service Phoenix AZ
437 PM MST Fri Jun 24 2022 .UPDATE... Updated 00Z Aviation .SYNOPSIS... Moisture will hang around with an even more favorable monsoon pattern setting up Sunday into next week. Today and tomorrow, winds and blowing dust will be the main weather risks, especially along I- 8 and I-10 in Maricopa, Pinal, and Yuma counties. Sunday and Monday, the flooding potential increases across the lower deserts as more moisture from soon to be Hurricane Celia advances towards the region. Low to moderate HeatRisk remains in place through next week. && .DISCUSSION... This morning, the 12Z sounding at Phoenix and Yuma, showed 1.37 inches and 1.23 inches of precipitable water respectively. This is a lot of moisture for this time of year with both of these values exceeding the daily maximum according to sounding climatology. The synoptic pattern remains nearly the same today, with slightly more westerly flow. An unstable atmosphere will be in place again today with mesoanalysis depicting MLCape values rising into the 500-1000 J/kg range across much of Maricopa, Pinal, and La Paz counties this afternoon. In these areas, DCape values will also be extremely high, in the 1800-2000 J/kg range. Convection will continue to develop across northern and eastern Arizona this afternoon, including southern Gila County, and be a little delayed across southern AZ (compared to yesterday). There is also a chance for lower desert storms, with a ~25% chance in the Wickenburg area, ~20% chance across the Phoenix and Casa Grande area, and <10% chance in Parker and Quartzite areas. Strong downburst/outflow winds and blowing dust will be the biggest risks today, especially along I-8 and I-10 in Maricopa and Pinal counties. The HREF probability of wind speeds exceeding 35 mph today is greater than 70% in southern Gila county, 50-70% in Maricopa and Pinal counties and 30-50% in La Paz county. Most areas will likely see less than a quarter inch of rain with storms. However, with plenty of moisture in the atmosphere to tap into, some cells may produce upwards of 0.5-1.0 inch of rain. Tomorrow, the area of focus shifts westward into western Pima, southern Maricopa, and Yuma counties, as this is where the best instability will be. The probability of greater than 35 mph wind speeds in this area is greater than 50%. HRRR 80m wind is also showing a decent outflow boundary developing and traveling northwest and potentially moving through southeast California. Strong downburst/outflow winds and blowing dust will be the biggest risks tomorrow in these areas, especially along I-8 in Yuma, Maricopa, and Pinal counties. We are still expecting a more favorable monsoon pattern to set up Sunday and last much of next week. It also appears that Sunday into Tuesday, we will see an increase in moisture from the tropics, thanks to soon to be Hurricane Celia. Thunderstorm chances in the Phoenix area rise to 25% each day Sunday into next week. Heavy rain, strong winds, and blowing dust will be the main risks each day. Moderate HeatRisk will remain in place for the lower deserts of our CWA through at least early next week. && .AVIATION...Updated at 2337Z. South-Central Arizona including KPHX, KIWA, KSDL, and KDVT: Gusty outflow winds and abrupt wind shifts from distant thunderstorms will be the greatest weather issues through Saturday evening under periods of mid/high cloud decks. Current 88-D radar imagery is showing storms developing over the higher terrain north of Phoenix and over SW Maricopa/Western Pima Counties. Current thinking is that outflows from the storms to the north will impact the Phx area terminals by early/mid-evening, then more typical easterly drainage winds return late this evening/overnight. However, confidence on this outcome is only moderate, an alternate scenario is that overflows from the storms to the south become dominant, with the outflows from the north washing out before they reach KPHX/KIWA. Confidence remains much lower (less than 20%) that thunderstorms actually directly affect any terminal, and have not included any mention in this TAF package. As far as Saturday is concerned, after continuing easterlies in the morning, the typical westerly switch is expected to occur around midday/early afternoon, with a possible switch back to easterly by mid-evening as outflows from distant storms once again move into the Phx area. Southeast California/Southwest Arizona including KIPL and KBLH: Little to no weather concerns will exist through Saturday afternoon under clear skies. Current southwesterly winds to become south- southeasterly late night/early Sat morning. A few gusts up to 20kt may be possible before decoupling overnight, and perhaps becoming light and variable Saturday morning. && .FIRE WEATHER... Moisture will remain entrenched across the desert southwest through next week. There will be daily opportunities for afternoon and early evening shower and thunderstorm activity, especially across Arizona and high terrain locations. With the increased moisture, MinRH values will remain above 15% across most areas through tomorrow and above 20% Sunday into all of next week. Great overnight recoveries. Apart from frequent late afternoon/early evening thunderstorm downburst and/or outflow winds, no other significant winds are expected. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...None. CA...None. && $$ DISCUSSION...Feldkircher AVIATION...Percha/18 FIRE WEATHER...Feldkircher
Area Forecast Discussion
National Weather Service Pueblo CO
322 PM MDT Fri Jun 24 2022 .SHORT TERM...(This evening through Saturday) Issued at 319 PM MDT Fri Jun 24 2022 Key Messages: 1) Convection pushing out into the eastern plains could lead to gusty outflow winds this afternoon and this evening. 2) Cold frontal passage early tomorrow morning will mark the start of a much wetter and cooler pattern for southern Colorado. 3) Flash Flooding risk increases throughout the day on Saturday. Currently.. As of 2:30pm local time, thunderstorms have developed over the La Garitas and the Central Mountains over the past few hours, and are starting to push northeastward into the foothills. The Air Force Academy is already seeing some light showers but lightning is still confined to the higher elevations at this time. The main threat with storms pushing into the I-25 corridor over the next few hours will be erratic outflow winds gusting up to 40 mph. Tonight.. Storms are not expected to be severe this afternoon, but DCAPE values of 1000-1200 J/Kg could lead to some 40-50 mph outflow winds on our eastern plains, especially in Kiowa, Bent and Prowers counties. These stronger storms look to push into Kansas by around 00-02Z this evening. Convection is expected to die off quickly after sunset in the mountains, but some weakening storms could linger until 04 or 05Z out on our plains. A cold front will push southward through Colorado late tonight, and pass through the northern extent of our forecast area (Teller and El Paso counties) any time after 3am Saturday morning. Temperatures will cool and dew point temperatures will rise behind this frontal boundary. Eventually upslope flow behind this front will bring about rain showers for late Saturday morning. Tomorrow.. Precip chances will lag behind the front for several hours, with the NAM nest not really hinting at showers or thunderstorms until after around 11am. Showers are expected to start in the San Juans and La Garitas, and spread from generally southwest to east-northeast into the San Luis Valley, the Central Mountains, and eventually into the Palmer Divide by around 6pm on Saturday evening. Both the HRRR and the NAM nest are showing strong signals that locally heavy rainfall will be possible tomorrow afternoon, especially along the Palmer Divide and the southern Sangres. The potential for flash flooding will increase throughout the evening, especially for burn scars in the Sangres. .LONG TERM...(Saturday night through Friday) Issued at 319 PM MDT Fri Jun 24 2022 Key messages: 1) Drastically cooler weekend with unsettled weather and a good amount of precipitation for much of southeast Colorado through Monday. Flash flooding will be possible Saturday night. 2) PM thunderstorms are going to be possible over the mountains and adjacent plains/I-25 corridor on Tuesday. Slight chance over central and eastern plains. 3) Better chance of widely scattered PM thunderstorms over most areas from Wednesday through Friday. 4) Temperatures are going to continue to gradually warm throughout the early part of week and back to the seasonal average by Wednesday. Detailed discussion: Saturday night through Monday... As the mid level major shortwave continues to move over the region, there is going to be and increase in lower level moisture advected within the cold pool behind the front. This will allow for a considerable amount of omega forcing along with favorable tall and skinny CAPE profiles over the eastern mountains with values of nearly 1200 J/kg. The combination of these meteorological elements will result in a fair amount of thunderstorm development and brief periods of heavy rain possible. Due to this, the potential of flash flooding will exist late Saturday evening through early Sunday morning, especially over the burn scar areas. With that being said, the clustering of the QPF is still spatially spread out and therefore confidence is lower for burn scar areas to be directly impacted. There is also a slight chance that fast rainfall accumulation rates could impact the urban areas of Pueblo and Colorado Springs. COS shows tall and skinny CAPE soundings in the morning, alluding to potential urban flooding rain within the downtown area. This is primarily due to the enhancement of lower level moisture along the I-25 corridor with some upsloping taking place by later in the night as winds continue to shift to being from a more easterly direction. The thunderstorms are going to transition more to a moderate and periodically heavier steady rain over much of the plains during the early morning on Sunday as isentropic accent increases over much of the area east of the Sangre de Cristo Mountains. Snow levels will also drop down to around 12,000 feet, so there could be rapid snow accumulations of several inches per hour on the highest peaks, with the Pikes Peak region looking to be the most favorable location to be impacted by this, based off the most recent model guidance. CAMs continue to show higher CAPE values to be confined to the mountains during the afternoon on Sunday, while remaining more stable over the plains with continued cooler air advection. This will keep a continuance of light to moderate rain over the plains, which will shift further south along the southern plains and Raton Mesa area. Over the mountains, destabilization and orographic lifting will allow for more development of convection by later in the afternoon. Low and mid level moisture content will be high, and therefore heavy rainfall rates could be possible again. Therefore, burn scars will need to be closely monitored again for the possibility of flash flooding. The San Juan Mountains could also receive copious amounts of rainfall in a short period of time as well. Much cooler air advection will keep temperatures much cooler and well below the seasonal average for this time of year, in fact, some locations over the plains could see record low maximum temperatures on Sunday. For instance, the record low max temp for Colorado Springs is 59 (set back in 2000) with a forecast high of 58, and the record max low temp for Pueblo is 64 (set back in 1937) with a forecast high of 64. On Monday, there is still going to be a fair amount of residual moisture in the mid levels to allow for more convection to develop, mainly over the mountains during the afternoon and then move out over the plains during the evening hours. The NAM 12 is showing areas of higher CAPE over the Palmer Divide area of nearly 2000 J/kg, indicating that this will be likely location for potentially stronger thunderstorms. There will also still be cooler air advection moving in out of the southeast over the plains with the troughing in place downstream to keep the plains relatively cool and below the seasonal average by anywhere from 10 to 15 degrees. Tuesday through Wednesday... The deterministic models are in general agreement that the moisture plume will shift back towards the west a little more as ridging subsequently builds back in over the region. Mid level flow will be more southerly so thunderstorm activity will primarily be confined to the mountainous regions with only some storms moving off over the adjacent plains and along the I-25 corridor later in the afternoon. On Wednesday, as troughing upstream begins to allow for the mid and upper level winds to become more southwesterly, the monsoonal moisture plume will remain in place and PM storms will have a better chance of moving off the mountains and over the plains. The ECMWF does tend to keep the plains drier than the GFS, but ensembles reflect areas of QPF over even the eastern plains. A gradual warming trend will occur due to the ridging, especially over the plains, with max temperatures returning to around the seasonal average by Wednesday. Thursday through Friday... Ensembles and deterministic models alike are in general consensus that the longwave trough upstream over the NW CONUS is going to continue to propagate to the east and north of the region. This will allow for the monsoonal moisture plume to get shifted back to the east again and also help to reinforce available moisture content and destabilize the mid levels, allowing for an uptick in thunderstorm development later in the afternoon and evening over most areas for both days. This troughing will also help to slowly bring back down max temperatures to slightly below the seasonal average over most areas by Friday. -Stewey && .AVIATION...(For the 00Z TAFS through 00Z Saturday evening) Issued at 319 PM MDT Fri Jun 24 2022 VFR conditions are expected at all three terminals for the next 24 hours. A cold front pushing through late tonight/early tomorrow morning will bring lowered ceilings and precipitation towards the beginning of the next TAF period. At KCOS.. Thunderstorm activity is within the vicinity of KCOS and is expected to move on station imminently. Spotty storms are continuing to redevelop southwest of station and will likely continue to keep tracking towards the terminals over the next few hours. The main threat with these storms will be erratic outflow winds gusting at 30-40kt. At KPUB.. Showers and weak thunderstorms are not expected to move on station this afternoon, but could be within the vicinity anytime between 22-01Z, especially north and west of station. The main threat with these storms will be erratic outflow winds that could gust up to 30kt. At KALS.. Showers and weak thunderstorms are expected to remain along higher terrain this afternoon. Confidence in lightning occuring on station or within 10nm of the terminal is low at this point, but gusty outflow winds up to 40kt will be possible this afternoon. && .PUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...EHR/SKELLY LONG TERM...STEWARD AVIATION...EHR/SKELLY
Area Forecast Discussion
National Weather Service Las Vegas NV
1151 AM PDT Fri Jun 24 2022 .SYNOPSIS...Isolated shower and storm activity will persist over northwestern Arizona through the weekend as the region taps into some early-season monsoonal moisture. Otherwise, temperatures will hover a few degrees above seasonal averages, with general afternoon breeziness expected through the forecast period. && .DISCUSSION...Today through Thursday. Another round of isolated shower and thunderstorm activity expected this afternoon, but will be restricted to the southern Sierra Nevada crest as well as Mohave County in Arizona. CAPE values in these areas will range from 500 to 700 J/kg this afternoon. Greatest anticipated impacts will be in Mohave County, where forecast HRRR inverted-V soundings show over 1200 J/kg of DCAPE with around 0.75" of PWAT. At least initially, rain that falls will struggle to reach the ground, due to evaporation through the dry low levels. Gusty outflow winds will be the primary concern. As showers persist and the column moistens, the potential for small hail will arise, with about 700 J/kg of mixed layer CAPE, though severe hail is unlikely. As mentioned in the previous discussion, Saturday`s convection looks to be very similar in nature to today`s as far as intensity, areal coverage, and location, though there is an increased chance of an isolated shower or thunderstorm in the panhandle of Lincoln County with modest CAPE values. Sunday, ridging builds over the area from the southeast Pacific, pushing convection opportunities further east. Though chances of isolated showers and thunderstorms persist for Mohave County through the early part of next week, chances will remain on the eastern fringes of the county, if initiating in Mohave at all. Meanwhile, temperatures will increase to a few degrees above seasonal averages across the Mojave and southern Great Basin deserts with general afternoon breeziness returning each day. "Moderate" HeatRisk expected below 5000 feet in elevation through midweek, meaning an increased risk of heat-related illness. Of note, Tropical Storm Celia persists in the southeastern Pacific Ocean, anticipated to develop into a hurricane early Saturday morning. Details will become more clear as we progress through the weekend, but depending on the exact track that Celia takes, coupled with the high pressure placement/eastward progression over the Four Corners, there may be enough of a moisture flux to increase PoPs over our forecast area mid-week. Though the NBM is not currently sold, the ECMWF ensemble means favor measurable precipitation across portions of southern San Bernardino County and up the Colorado River Valley, with PWATs between 1.00 and 1.50 inches. Stay tuned! && .FIRE WEATHER...Fire concerns remain concentrated to Mohave County as well as the southern Sierra today. In the Sierra, the primary hazard will be dry lightning strikes. Though gusty winds are possible from area thunderstorms, afternoon RH values will range from 30 to 40 percent, helping to mitigate fire concerns. Across Mohave County, dry lightning as well as afternoon RH values in the single-digits on the western side of the county - increasing to lower 20s on the eastern fringes - will be present alongside gusty outflow winds from storms that develop. Storm potential greatly diminishes with sunset. && .AVIATION...For Harry Reid...Breezy south to southwest winds are expected this afternoon, with gusts 20-25KT expected. Winds will dissipate after sunset, with typical overnight wind trends expected tonight. Diurnal winds trends are likely for Saturday with wind speeds of 8KT or less. Occasional afternoon clouds around 12kft are possible, otherwise skies will be clear through the period. For the rest of southern Nevada, northwest Arizona and southeast California...Isolated convection is possible in western Arizona this afternoon as well as along the Sierra ridgeline. Any thunderstorms could contain lightning and sudden gusty winds. Elsewhere, it will be dry today. Expected breezy south to southwest winds with gusts 20- 25KT this afternoon. Any thunderstorms that develop this afternoon will dissipate this evening. Mostly clear skies and typical wind trends return for tonight and Saturday morning across the region. && .SPOTTER INFORMATION STATEMENT...Spotters are encouraged to report any significant weather or impacts according to standard operating procedures. && $$ DISCUSSION...Varian AVIATION...Nickerson For more forecast information...see us on our webpage: or follow us on Facebook and Twitter