Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 07/29/24


Area Forecast Discussion...UPDATED
National Weather Service Albuquerque NM
525 PM MDT Sun Jul 28 2024 ...New AVIATION... .SYNOPSIS... Issued at 205 PM MDT Sun Jul 28 2024 Showers and thunderstorms will be mostly confined to mountain locations south of Interstate 40 Monday afternoon. The exceptions will be over the Sangre de Cristo and Jemez mountains where isolated showers and storms remain possible. For Tuesday and Wednesday, thunderstorm activity will trend up slightly over most mountain ranges, attempting to spread into valley locations during the late afternoon and evening, but struggling to survive for very long. The monsoon high, currently over southeast NM, is forecast to drift back toward the Four Corners on Thursday and Friday, resulting in a surge of near surface moisture from the east with the possibility of widespread showers and thunderstorms returning to the area Friday and Saturday. Additionally, the thermostat will get turned up Wednesday and Thursday afternoons as the monsoon high strengthens over NM on its journey back to the Four Corners region and eventually the Great Basin by next weekend. && .SHORT TERM... (This evening through Monday night) Issued at 205 PM MDT Sun Jul 28 2024 Drier air invading northern NM per water vapor loop has played a significant role in the reduction of showers/storms for areas along and north of Interstate 40. Meanwhile, slow-moving activity will be favored over the west central, southwest and south central mts and adjacent lower elevations. With the upper high centroid traversing the southern zones from west-east today/tonight, expect motions to be slow and erratic. Unfortunately, this will not bode well for the burn scars in Lincoln County. The latest HRRR is still advertising an organized outflow boundary originating from the upper Gila region tracking northward into the central zones and this could make things a tad interesting for the RGV. This may be enough to support stray showers late this afternoon and early evening. Models indicate most of the convection should wind down by midnight. Overall, expect low temperatures to be a few degrees above normal. For Monday, the aforementioned upr high will continue its eastward migration into north central TX. This will place NM on the western periphery of this circulation, which will slowly erode away the dry air across the northern zones. The best convective coverage remains in the west central and southwest mts, and isolated storms over the northern mts can be expected. Storm motions will still remain slow, but will have more a north-northeast trajectory given the position of the upr high. Overall, the risk for flash flooding should remain the same with the primary message: low probability, but high impact scenario for our most sensitive scars in Lincoln County. Meanwhile, heat risk impacts will increase, particularly from eastern Union to Chaves counties, including Clayton, Tucumcari, Clovis/Portales and Roswell. Heat Advisory criteria in these areas is 105F. The NBM has projected a 53% chance of meeting this criteria at Roswell and 13% at Tucumcari. Will not issue headlines at the moment, but that does not discount the heat-related risks for these areas. DPorter && .LONG TERM... (Tuesday through Saturday) Issued at 205 PM MDT Sun Jul 28 2024 Weather prediction models remain in good agreement with regard to Tuesday and Wednesday, shifting the center of the monsoon high eastward over the Red River Valley of north TX and southern OK. South and southwest winds on the western periphery of the high will draw up additional low and mid level monsoon moisture into areas primarily west of the central mountain chain Tuesday and Wednesday. Mid level (700-500 mb) lapse rates of 8.3C/km from the NAM12 remain indicative of storms that will struggle to survive for long without plentiful outflow boundary interactions given the limited surface moisture progged for Tuesday afternoon. Moisture increases Tuesday night and Wednesday for better chances of showers and storms in valley and basin locations during the late afternoon and early evening. Scattered thunderstorms are forecast elsewhere along and west of the Sangre de Cristo mountains and central highlands on Wednesday. Atmospheric moisture content (precipitable water or PWAT) is forecast by the NAM12 to increase to above average levels for late July on Wednesday, so the storms that develop will be capable of producing torrential rainfall rates upwards of 2" per hour. Thursday remains quite the intriguing day with a backdoor front, plentiful low level moisture, and a monsoon high center migrating to the northwest over NM. Weak storm steering flow aloft and copious low level moisture will likely result another day where storms over most if not all mountain ranges become torrential rainers. Friday continues along those same lines, but with more storm coverage forecast and slightly stronger steering flow with a monsoon high center directly over northern NM. The high eventually migrates back over UT next weekend for a continued active period for central and northern NM. Light to moderate northeasterly shower and thunderstorm steering flow is forecast. && .AVIATION... (00Z TAFS) Issued at 521 PM MDT Sun Jul 28 2024 Isolated storms are slowly drifting around southwestern and south-central NM this hour. Little to no impact is expected from these cells at any TAF terminal this evening. VFR prevails overnight with another relative down day for afternoon showers and storms Monday. A rogue storm developing along the Continental Divide may have a chance to reach KGUP, but confidence is too low this far out to include a mention of this just yet. LLWS will again be present at KTCC, and to lesser extent below TAF criteria at KROW at 015/18025kt. && .FIRE WEATHER... Issued at 205 PM MDT Sun Jul 28 2024 Critical fire weather conditions are not anticipated over the next seven days. For the early portion of the work week, very hot temps will favor central and eastern NM with readings stretching from the upper 90s to mid-100s. Best chances for wetting pcpn will be across the west central high terrain, and this will expand slowly east and north through midweek. Storm motions will remain relatively slow as they track north-northeast. All storms will be capable of gusty and erratic outflows. The upper high will migrate back toward the Four Corners region with a backdoor front invading the ern plains on Thu. This will likely increase precipitation chances areawide along with higher humidities and cooler temperatures. DPorter && .PRELIMINARY POINT TEMPS/POPS... Farmington...................... 63 92 64 93 / 0 5 10 5 Dulce........................... 48 90 50 91 / 0 5 10 20 Cuba............................ 57 89 59 89 / 5 10 20 30 Gallup.......................... 56 90 56 90 / 10 20 20 20 El Morro........................ 58 85 57 84 / 30 40 30 50 Grants.......................... 60 89 60 89 / 20 30 20 40 Quemado......................... 59 85 58 86 / 40 60 40 70 Magdalena....................... 63 88 64 88 / 30 30 20 40 Datil........................... 58 85 57 84 / 30 60 30 70 Reserve......................... 57 90 56 91 / 50 70 30 70 Glenwood........................ 66 95 67 94 / 40 60 30 60 Chama........................... 51 83 52 84 / 0 10 10 30 Los Alamos...................... 64 87 66 87 / 5 20 10 40 Pecos........................... 61 89 62 89 / 0 20 10 40 Cerro/Questa.................... 51 86 53 87 / 0 20 10 40 Red River....................... 49 77 51 78 / 0 20 10 40 Angel Fire...................... 44 81 46 81 / 0 20 10 40 Taos............................ 54 90 55 91 / 0 10 10 20 Mora............................ 55 85 56 87 / 0 20 10 40 Espanola........................ 61 95 62 95 / 0 5 10 10 Santa Fe........................ 64 90 65 90 / 5 10 10 30 Santa Fe Airport................ 61 93 63 94 / 5 5 10 20 Albuquerque Foothills........... 70 95 71 95 / 10 10 10 30 Albuquerque Heights............. 68 97 69 96 / 10 5 10 10 Albuquerque Valley.............. 67 98 69 98 / 10 5 10 10 Albuquerque West Mesa........... 68 96 69 97 / 10 5 10 10 Belen........................... 65 97 66 98 / 20 5 20 10 Bernalillo...................... 68 99 69 98 / 10 5 10 10 Bosque Farms.................... 64 97 66 98 / 20 5 10 10 Corrales........................ 68 99 69 98 / 10 5 10 10 Los Lunas....................... 66 97 67 98 / 20 5 10 10 Placitas........................ 67 95 67 94 / 10 5 10 20 Rio Rancho...................... 68 98 69 96 / 10 5 10 10 Socorro......................... 68 99 69 99 / 20 10 20 20 Sandia Park/Cedar Crest......... 63 89 64 89 / 10 10 10 30 Tijeras......................... 64 91 65 91 / 10 5 10 30 Edgewood........................ 59 92 61 91 / 10 10 10 20 Moriarty/Estancia............... 57 94 58 92 / 10 10 10 20 Clines Corners.................. 59 90 61 90 / 5 10 10 20 Mountainair..................... 60 91 61 91 / 10 10 20 20 Gran Quivira.................... 61 91 61 91 / 10 10 20 30 Carrizozo....................... 67 95 67 95 / 20 20 20 20 Ruidoso......................... 61 86 61 87 / 20 30 20 40 Capulin......................... 59 89 61 90 / 0 5 5 20 Raton........................... 56 92 59 94 / 0 5 0 10 Springer........................ 56 94 58 95 / 0 5 5 10 Las Vegas....................... 57 90 58 90 / 0 10 10 30 Clayton......................... 66 99 68 100 / 5 0 5 5 Roy............................. 61 95 63 95 / 0 5 5 10 Conchas......................... 66 102 69 103 / 5 0 5 0 Santa Rosa...................... 65 98 66 97 / 5 0 5 5 Tucumcari....................... 69 103 71 102 / 0 0 5 0 Clovis.......................... 69 101 71 102 / 0 0 5 0 Portales........................ 69 102 70 102 / 0 0 5 0 Fort Sumner..................... 69 102 70 102 / 5 0 5 0 Roswell......................... 73 104 74 105 / 5 0 5 0 Picacho......................... 66 97 66 97 / 10 5 10 5 Elk............................. 63 95 63 95 / 20 10 10 20 && .ABQ WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...46 LONG TERM....33 AVIATION...24
Area Forecast Discussion
National Weather Service Aberdeen SD
622 PM CDT Sun Jul 28 2024 .KEY MESSAGES... - There is a Slight Risk (level 2 of 5) for severe storms late this afternoon through midnight or so. The main threat with the strongest storms will be wind gusts in excess of 70 mph, but large hail and a tornado or two are also possible. - There is a Slight Risk (level 2 of 5) for severe storms late Monday afternoon and Monday evening. The main threat with the strongest storms will be large hail and strong wind gusts. - Elevated smoke from Canadian and western wildfires will continue to result in a milky sky with filtered sunshine. && .UPDATE... Issued at 618 PM CDT Sun Jul 28 2024 Thus far have a few towers go up but nothing has been well maintained more than a few scans. CAMS still support convective development, though the HRRR is suspiciously quiet. Will continue to watch for convective development, however while there is a weak wave to support convection, there isn`t a low level jet to focus and maintain it overnight. See below for the update to the Aviation discussion... && .SHORT TERM /THIS EVENING THROUGH MONDAY NIGHT/... Issued at 316 PM CDT Sun Jul 28 2024 An upper level shortwave and associated energy will track across the CWA this evening. A more zonal flow will set up on Monday before another shortwave moves through late Monday afternoon and Monday evening. At the surface, a frontal boundary is currently situated from southwestern South Dakota to southeastern North Dakota. There has been some shower and weak thunderstorm activity off an on all day, mainly to the north of the front. The front will gradually work its way eastward and will become almost more north/south oriented over eastern South Dakota this evening. Will likely see some thunderstorm development over central South Dakota by early evening, then will see additional development as the front encounters more unstable air over eastern South Dakota and west central Minnesota later this evening. MUCAPE values will generally be in the 1500-3000 J/kg range. Shear will not be real strong, generally in the 20 to 30 knot range in association with the instability, but it will be in the 30 to 40 knot range just west of the front. Some of the CAMS are more robust than others with the areal coverage of storms, but all agree that chances are pretty good for storms somewhere over the CWA this evening, before they exit the CWA to the east around or shortly after midnight. The biggest threat with the stronger storms will be wind gusts in excess of 70 mph, but large hail and a tornado or two are also possible. High pressure moves in late tonight and Monday morning, bringing a brief respite in the precipitation. Another frontal boundary then looks to track across the area Monday afternoon and evening, and will be the focus for additional thunderstorm development. The instability and shear will be a bit more in line across the east, with 2000-3000 J/kg of MUCAPE and 40 to 45 knots of shear. Steep lapse rate will aid in more of a large hail threat, but strong winds gusts cannot be ruled out. Low temperatures tonight will be in the 60s. High temperatures on Monday will be in the upper 80s to lower 90s. Lows Monday night will again be in the 60s. && .LONG TERM /TUESDAY THROUGH SUNDAY/... Issued at 316 PM CDT Sun Jul 28 2024 No major model changes to the overarching long wave pattern in the long term period. Also no distinct clustering differences among the ensembles 500 MB pattern. Upper level high pressure will be over the south central CONUS with a low amplitude ridge extending across the central and northern plains states on Tuesday. This will be short lived as a distinct trough approaches from the west late Tuesday-Wednesday. This will initially place us in southwest flow aloft before the trough passes late Wednesday into Thursday. At the surface broad low pressure will be lingering through this time frame with a persistent southeast flow allowing dewpoints to easily range from the mid 60s to mid 70s. In fact, the NBM probability of 70 degree dewpoint temps ranges from 60-80% along and east of the James River. It is readily easy to infer plenty of instability through the time frame. The big question then becomes, when and where will thunderstorms develop. A robust CAP will likely prevent any surface based activity on Tuesday. The only exception might be the far northeast CWA where 700 MB temperatures only have a 30-50% chance of exceeding 12 C. Elsewhere, however, very good chances (60- 100%) of this mid level warm air being positioned over the region. Most models are hinting at a shortwave providing enough forcing/cooling overnight Tuesday into Wednesday morning for thunderstorm development. A very similar set up late Wednesday into Thursday morning with the main trough passage. The northern plains will return to more of a northwest flow pattern Friday and through the weekend due to building southwest CONUS high pressure. While it was mentioned that there are no distinct clusters in the long wave pattern, we are still seeing the persistent GEFS bias toward excessive mixing/warm bias. NBM temperatures seem to handle this bias well and no changes made to the blended guidance. Temperatures will remain above normal (upper 80s-upper 90s) through the end of the work week, with a trend toward more seasonal temperatures by the weekend. && .AVIATION /00Z TAFS THROUGH 00Z MONDAY/... Issued at 618 PM CDT Sun Jul 28 2024 Terminals KABR,KATY,KPIR,KMBG VFR conditions for all terminals, though there is the potential for fog formation at the KATY terminal during the early morning hours. Otherwise best potential for storms on station will be at KABR/KATY through the evening. && .ABR WATCHES/WARNINGS/ADVISORIES... SD...None. MN...None. && $$ UPDATE...Connelly SHORT TERM...Parkin LONG TERM...Serr AVIATION...Connelly
AREA FORECAST DISCUSSION
National Weather Service Wakefield VA
743 PM EDT Sun Jul 28 2024 .SYNOPSIS... Pleasant weather continues this evening as high pressure remains over the area. A warming trend is expected next week along with daily chances for showers and thunderstorms. && .NEAR TERM /UNTIL 6 AM MONDAY MORNING/... As of 740 PM EDT Sunday... Key Message: - Dry and pleasant this evening. - High clouds building in tonight with lows in the mid-upper 60s. High pressure at the sfc persists over most of the East Coast. Meanwhile, a closed UL low is located off the coast of southern New England, placing northerly flow over the Mid-Atlantic aloft. Temperatures have started to drop off with the loss of heating. Overnight, sfc high pressure will slide just offshore and a shortwave aloft will approach the region from the W/SW. Ahead of the disturbance, high clouds will build in from the SW to NE late tonight into tomorrow. With increasing cloud cover and sfc flow switching around to the S, lows will not be quite as cool as they were last night, but still dropping into the mid-upper 60s. && .SHORT TERM /6 AM MONDAY MORNING THROUGH WEDNESDAY NIGHT/... As of 330 PM EDT Sunday... Key messages: -A more unsettled pattern returns Monday with daily chances for showers/storms lasting through the week. -Highest coverage of precip looks to be Tuesday/Tuesday night The closed off low aloft will move back into New England Monday with a coupled low at the sfc. Sfc high pressure will remain offshore. A series of disturbances aloft will bring daily chances for showers and storms. Precip on Monday looks to be largely limited to western and northern counties. CAMs have decent agreement in isolated to scattered storms moving in from WSW Monday afternoon as the first shortwave moves into the area. Precip likely dies out in the evening hours. CAMs do suggest some redevelopment of showers/storms late in the night (04z-08z) somewhere along or E of I-95 as a second shortwave pivots through the area with the 12z HRRR being the most aggressive on this solution. Highs on Monday still in the 80s. Will likely stay in the low-mid 80s in the SW where cloud cover will be thicker and precip starts earlier. Elsewhere, mid-upper 80s expected. Additional showers/storms are expected Tuesday. A shortwave along with a trough axis aloft will likely mean Tues will likely have the highest coverage of storms for the week. Have introduced some likely PoPs, but these are still limited to the NW counties. High temps a degree or two cooler Tuesday as more clouds are forecast, with mid 80s for most of the CWA. Any leftover convection may slowly move E through the evening and will keep low-end chance PoPs through the night along the coast. Lows 70-74. A trough axis remains over the E Coast Wed. This, combined with hot, humid conditions will lead to additional storms Wed afternoon/evening, though confidence in coverage is lower. Keeping 30- 45% PoPs across the area with highest PoPs in the SE. Wed starts a period of hotter weather with highs around 90. Lows Wed night in the low-mid 70s. && .LONG TERM /THURSDAY THROUGH SUNDAY/... As of 330 PM EDT Sunday... Key Messages: - Chances for showers and thunderstorms are expected each afternoon/evening. - Heat builds to end the work week, with heat indices approaching heat advisory criteria. Remaining somewhat unsettled moving into the extended period with daily chances for mainly afternoon/evening convection. The synoptic pattern will be characterized by a broad trough over the E CONUS Thurs before the trough weakens and shifts offshore late in the week. This will set up westerly or NW flow aloft. Weak disturbances in the flow aloft and daily sfc troughing will likely act to spark showers and storms. It remains difficult to confidently say which areas and days favor the highest coverage of rain, though Thursday looks to be driest day with only Schc PoPs in the forecast for most of the area. Global models continue to show MCS activity developing upstream over the Midwest each day and while most of this would be expected to stay or decay W of the area, will need to keep an eye on this as we get closer in case any of these act to spark any convective activity nearer to our area. By Friday and into the weekend, a more defined trough may approach from the NW and some stronger mid- level flow overspreads the area. May therefore need to keep an eye out for some stronger storms then (machine learning tools beginning to show a potential uptick in the wind threat). Still a week away so uncertainty is obviously higher. Aerial QPF is forecast to average 0.75"-2" in the day 1-7 period, so not as wet as the previous unsettled period. It will be noticeably warmer Thursday and Friday, with afternoon dew points also increasing well into the 70s. Highs in low-mid 90s Thursday, and mid 90s Friday and Saturday. Heat indices also creep back up to 100- 105+ F and we could be looking at a round of heat headlines Thursday and especially Friday. Forecast overnight lows are in the 70s. && .AVIATION /00Z MONDAY THROUGH FRIDAY/... As of 740 PM EDT Sunday... VFR conditions prevail through 00z TAF period with high pressure over the region. Winds are generally from the S around 5 kt, becoming light and variable tonight. Mostly clear skies expected until some mid and high clouds move into the region late tonight toward sunrise on Monday. SW winds 5-10 kt are expected tomorrow with some gusts to 15-20 kt possible, especially at RIC. Outlook: Isolated showers/storms may impact the western half of the area Monday evening with potential for MVFR/IFR CIGs in the Piedmont Monday night. Unsettled pattern returns with increased chances for afternoon and evening storms through mid week. && .MARINE... As of 315 PM EDT Sunday... Key Messages: - Generally sub-advisory conditions continue through Tuesday although a SSW wind will increase each night. - SCA conditions are possible Tuesday night into Wednesday due to an increasing SSW wind. High pressure is located along the coast this afternoon, leading to light and variable winds over the Chesapeake Bay/tidal rivers and sea-breeze dominant along the Atlantic coast. High pressure nudges offshore later this evening into tonight, with the wind becoming S 10-15kt north and 5-10kt south. The wind becomes SW 10-15kt with gusts near 20kt and SW ~10kt south by early Monday morning. Seas will linger ~3ft off the Currituck Outer Banks through this afternoon, with 2-3ft seas elsewhere, and 2-3ft for the entire coastal waters tonight. Waves in the Bay will generally be ~1ft today, and then build to ~2ft tonight and 2-3ft in the middle Bay. High pressure settles offshore Monday and remains off the Southeast coast through at least later this week. The wind becomes SSW 10-15kt with occasional gusts to ~20kt for the ocean/Bay tomorrow into tomorrow night and will typically strongest during the late afternoon and evening hours. The best chance for marginal SCA conditions will be Tuesday evening into early Wednesday as weak low pressure passes northwest of the waters, tightening the pressure gradient. SSW winds will increase to 15 to 20 knots with gusts of 20 to 25 knots possible. Local wind probs are indicating ~50-60% chance for 20+ knot gusts over the Chesapeake Bay Tuesday night. The pressure gradient slackens to some extent Wednesday through later this week with a SSW wind mainly 10-15kt for the ocean and Bay, and 5-10kt elsewhere. Seas will mainly be 2-3ft Monday through much of next week, although seas build to 3-4ft (possibly 5ft out 20 nm) Monday night into Tuesday night N of Parramore Is and again Tuesday night into Wednesday with the enhancement of the SSW wind. Waves in the Ches. Bay will mainly be 1-2ft for much of the period, and 2-3ft in the middle Bay Monday night and Tuesday night. Chances of primarily aftn/evening showers/tstms return Monday through most of the week. Rip Currents: For Monday, a moderate risk is forecast for the northern beaches with an increasing SSW wind and nearshore waves building to ~3ft. A moderate risk is also forecast for the Currituck Outer Banks beaches, with a low risk in Virginia Beach. On Tuesday, a moderate risk is again forecast for the northern beaches, with a low risk south. && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...None. NC...None. VA...None. MARINE...None. && $$ SYNOPSIS...SW NEAR TERM...AM/RHR SHORT TERM...AM LONG TERM...AM/SW AVIATION...RHR MARINE...AJB
Area Forecast Discussion
National Weather Service La Crosse WI
1051 PM CDT Sun Jul 28 2024 .KEY MESSAGES... - Scattered showers end by early evening then shower/storm chances increase overnight into Monday. Off and on storm chances persist through Thursday as the heat keeps its grip over parts of the Rockies and the central and southern Plains. Any convective complexes through the week could affect temperatures depending on their timing and how long the clouds hang on. - Heat index values are expected to be in the 80s and 90s Monday through next Sunday with Wednesday being warmest. Warmest wet- bulb globe temperatures are mostly in the 70s to lower 80s. At these levels, we remain in a risk level 1 to 2 of 4 for heat risk; Minor to Moderate for heat sensitive individuals. && .DISCUSSION... Issued at 255 PM CDT Sun Jul 28 2024 Overview: Morning water vapor satellite imagery, 500mb heights, and lightning showed an open wave over parts of Iowa/Missouri with northern embedded shortwave troughs within the southwest flow aloft from the West Coast through the Plains into Ontario. The Gulf was open with mid and high level moisture streaming northward through the Mississippi Valley River states. Multiple clusters of storms were noted from KS/NE/Dakotas into northern MN and Ontario. This is a bit messy with so many embedded vorticity maximums. The thunder with the clusters was noted where the low level jet was stronger; in the 30 to 45kt range. The 19Z Visible satellite imagery showed a cumulus field over the forecast area with an mesoscale vorticity center over northwest Iowa. The 19Z subjective surface analysis had the surface boundary to the west from northern WI to the Dakota with a surface trough through the western High Plains. Temperatures had warmed into the upper 70s to mid 80s with sticky dewpoints in the upper 60s to lower 70s. Showers over southern WI earlier in the morning continue to be more prevalent across south central and southeast WI with the moisture transport and to the northwest and southwest over parts of MN and Iowa. The latest WSR-88D mosaic had showers mainly over southern WI with clusters of storms over north central MN and northeast Neb. into northwest IA. Showers/Storms Through Tuesday: Multiple pieces of energy will try to converge tonight into Monday as shortwave troughs move east across the Northern Plains and energy from western Iowa slides east. The 25kt 900mb low level jet over the Missouri River Valley is forecast to strengthen 30 to 50kts overnight. The stronger axis of winds is across Kansas into Missouri with weaker, more focused 30 to 40kts winds into Iowa and southeast MN Monday morning. Will need to continue to monitor the MCV to the west. The 18Z HRRR and RAP have increased the cells develop a little farther north into northeast Iowa earlier. Rain chances increase from the west overnight spreading east Monday morning. The low level jet weakens 15-18Z, so should see an overall decrease in coverage. Rain appears likely for much of the area, but due to the focused forcing in some areas and not so much in others, rainfall could vary from trace- 0.10" in spots to .5 to 1" in others. With heating during the day and the upper level trough over the area, there should be an uptick is coverage and intensity with precipitation ending from west to east as the trough shifts east. We remain in a severe weather risk level 1 of 5 Mon. Stronger storms could develop with heating, but the instability and shear appear more favorable south of the local area. Precipitable water values of 1.5 to 2" will accompany the storms with warm cloud depths in excess of 4km. Storm motions vary from 5 to 15 or 20kts, thus locally heavy downpours of rain could occur Monday. The next upstream wave over the Dakotas Monday is forecast to push into the area Tuesday as mid-tropospheric ridging is also trying to build east. There is sufficient mid level moisture, but weakening forcing. The deterministic and hi-res models are mostly dry with spotty precipitation. Our current forecast is dry, but did add pops for spotty/storms with the elevated instability around 3000 J/kg as it may be on the periphery of the cap. As we refine the timing and location of potential convection, we can further increase pops. Above normal temperatures and uncomfortable humidity with highs in the 80s Monday and 80s to lower 90s Monday. The Extended: Still unsettled Wednesday and Thursday with multiple pieces of energy with the next trough. The warmer capping 700mb temperatures remain to our west, thus we remain vulnerable to mesoscale convective complexes on the periphery of the ridge. There continues to be a signal for an MCS or two affecting parts of the local area. There is not good model agreement in how these evolves at this time, but at least the potential for some beneficial rain for some. Ridging builds in for Friday through Sunday with normal to above normal highs in the 80s. Our current forecast is dry, but will need to monitor for shortwaves moving across Canada into the Northern Plains which could touch off storms. Heat this Week: Heat index values are in the 80s and 90s Monday through next Sunday with Wednesday being warmest. Warmest wet-bulb globe temperatures are mostly in the 70s to lower 80s. At these levels, we remain in the level 1 to 2 of 4 for heat risk; Minor to Moderate for heat sensitive individuals. && .AVIATION /06Z TAFS THROUGH 06Z TUESDAY/... Issued at 1045 PM CDT Sun Jul 28 2024 It is a low confidence aviation forecast for tonight as multiple weak shower and thunderstorm complexes shift through the region. Did add showers early on in the TAFs where confidence in occurrence is higher and VCSH through the mid- morning hours before the weather system departs. Ceilings and visibilities will hinge on how storms evolve overnight, with the greatest potential of restrictions staying south of the TAF sites. Did add an MVFR ceiling mention to account for the possibility of restrictions, but there is a 20-30 percent chance that we see IFR or LIFR conditions, mainly towards RST. Restrictions improve quickly by mid-morning with VFR conditions expected for the rest of the TAF period. Winds will generally be around 5-10 kts and veering from the south to west in the afternoon. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...None. MN...None. IA...None. && $$ DISCUSSION...Zapotocny AVIATION...Skow
Area Forecast Discussion
National Weather Service Birmingham AL
753 PM CDT Sun Jul 28 2024 ...New SHORT TERM, AVIATION... .SHORT TERM... (Tonight through Tuesday) Issued at 726 PM CDT SUN JUL 28 2024 Relatively slow moving thunderstorms and thunderstorms moving over the same locations more than once produced rainfall amounts of 3-5 inches in several locations today. Due to the tropical airmass overhead, the rainfall rates were extreme and some flash flooding was observed. The latest radar depiction has thunderstorms from near Birmingham to Selma and westward to near Linden. This activity will move west to east and was associated with lift from a passing short wave trough. The latest RAP analysis has the south and east as the other areas no worked over by convection earlier in the day. Therefore, expect the storms to continue moving west to east this evening and potentially make it to the Georgia state line. The current pops have less chances far southeast and will monitor this closely the next hour or so before possible increase. It appears that another short wave trough moves into the area toward daybreak and there will be increased rain chances again late tonight and into Monday. The storms overnight may still produce locally heavy rain, with some areas receiving torrential rainfall. Some locations may receive 3-4 inches of rain. Made some adjustments to the pops and temperature trends. 75 Previous short-term discussion: (This evening through Monday) Issued at 117 PM CDT SUN JUL 28 2024 Monday. Broad mid-level ridging will continue to amplify over the Southern Plains while a longwave trough extends from over Wisconsin southeast to over Indiana as the offshore coastal storm impacts from New York City to Boston. A northwesterly flow pattern will develop aloft over the area with a few shortwaves depicted in modeling during the day Monday moving southeast over the area. Surface high pressure will be found off of the Carolina coastline while low pressure will persist across the Central Plains and Midwest. Mostly cloudy skies with chances for showers and some thunderstorms will be higher across the eastern half of the area Monday while lower chances will be found to the west. Winds will be from the west to northwest at 4-8 mph and high temperatures will range from the mid 80s in the higher elevations northeast to the low 90s west and southwest. The combination of temperatures with dew point values in mid 70s will result in heat index readings peaking from 100-102 degrees across the southwest third of the area during the early to mid afternoon hours. 05 && .LONG TERM... (Monday night through next Saturday) Issued at 237 PM CDT SUN JUL 28 2024 Key message: - A hotter and drier overall trend is emerging through the end of the upcoming week. Dangerous heat indices between 105 and 109 degrees will be possible as highs top out in the mid to upper 90s starting Tuesday and potentially lasting through Saturday. The upper level ridge will continue to build to our west over Texas on Tuesday as the main upper trough axis ejects eastward toward the Eastern Seaboard. A 500mb vort max will track southeastward within the northwest flow that will trigger scattered to perhaps numerous showers and storms primarily over the eastern half of Central Alabama. Guidance this afternoon is trying to keep most convective activity more toward the east, and have adjusted PoPs accordingly to reflect those trends. The upper level ridge will build close to 597 decameters into the lower Mississippi Valley by Wednesday afternoon, with rain chances decreasing as a result. Still, diurnally-driven scattered showers and storms will be possible across the eastern and southeastern counties. Additional upper level shortwave impulses moving southward along the eastern periphery of the ridge will help to synoptically support that development as well. At least scattered convection will be possible during the afternoon hours through the end of the forecast period. The biggest story during the long-term forecast will be the building heat, that will likely become a long-duration event. Starting Tuesday, low-level moisture will remain elevated with southerly to southwesterly flow at the surface. Dewpoints will be hard pressed to mix down into the mid 70s during peak heating hours Tuesday through Friday and potentially lingering into Saturday as well. Heat indices will likely rise between 105 and 109 degrees in many locations, and Heat Advisories will be needed if current guidance trends hold up for much of Central Alabama for at least 4 days in a row. At the end of the period, long-range guidance is hinting at a trough digging over the eastern CONUS with a front headed our way as of the 12z runs. 56/GDG && .AVIATION... (00Z TAFS) Issued at 726 PM CDT SUN JUL 28 2024 Convection was affecting several terminals this evening. Near the northern sites, the activity was beginning to weaken and become elevated. The lightning that was occurring was sporadic and mainly positive. Near MGM, active thunderstorms will move into the area from 01-03z moving west to east. Some of the rainfall may be torrential. VFR conditions were common outside of the convection with scattered low clouds and VFR ceilings. Another area of lift will approach toward daybreak increasing rain chances north. The high rain chances spread to a large part of the area on Monday. Most terminals will experience the IFR/LIFR ceilings around 12z lasting a few hours. Ceilings then rise through the morning but will be impacted by the rain chances moving back in. Winds will be light and variable overnight and most likely display a westerly component on Monday. 75 && .FIRE WEATHER... A humid airmass will remain in place through the first half of the upcoming week as high pressure builds into the area. Winds will become more southwesterly to westerly Monday through Tuesday. && .PRELIMINARY POINT TEMPS/POPS... Gadsden 71 87 73 92 / 80 80 40 60 Anniston 72 87 73 91 / 80 90 40 60 Birmingham 74 87 75 92 / 70 80 30 50 Tuscaloosa 73 91 75 94 / 60 50 20 40 Calera 73 88 75 93 / 80 80 20 50 Auburn 73 87 74 91 / 70 90 30 70 Montgomery 74 91 75 93 / 80 70 20 60 Troy 73 89 73 93 / 70 70 20 70 && .BMX WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...75 LONG TERM....56/GDG AVIATION...75
Area Forecast Discussion
National Weather Service State College PA
1034 PM EDT Sun Jul 28 2024 .SYNOPSIS... Low pressure will meander south of New England before an upstream shortwave nudges it to northern New England and Quebec Monday night and Tuesday. Another disturbance will track just north of Pennsylvania late Tuesday into early Wednesday, followed by a slow-moving cold front will approach the area by the end of this week. && .NEAR TERM /UNTIL 6 AM MONDAY MORNING/... Despite the seasonably unusual area of low pressure south of New England, sfc pressures are higher to our east this evening, resulting in easterly wind shifts at many sfc observing stations earlier this evening before post-sunset decoupling. Mid to high clouds continue to spill into eastern parts of our forecast area late this evening. Overnight forecast is fairly steady state. Mostly clear skies will prevail across the western two thirds of the state with those high clouds eventually covering the eastern third of central PA. The combination of mainly clear skies, light wind, and still relatively dry air over PA supports undercutting NBM min temps tonight again by a couple of degrees. Although it will not be as cool as recent nights, patchy valley fog is possible over the valleys of Northern PA, where USGS gages indicate water temps of 24C to 26C. && .SHORT TERM /6 AM MONDAY MORNING THROUGH WEDNESDAY/... On Monday, Central PA will be wedged between an upper low over Southern New England and a shortwave working up the Ohio Valley on Monday. The upstream shortwave will nudge the sfc low northward to Northern New England and Quebec by late Monday night and Tuesday. But in between, large scale subsidence between these features is likely to result in a mostly rain-free and very warm day across most of the forecast area. However, the light southerly flow will continue to advect increasing low level moisture into the state and the approaching shortwave and surface warm front could support a late day shower/tsra across the southwest part of the forecast area. GEFS 2m temp anomalies indicate highs should be 4-7 degrees above average across the Central Mtns, while a cirrus shield associated with the upper low may temper the heat across the eastern counties. Max temps should range from the upper 80s to low 90s over most of the area, with spot mid 90s possible over parts of the South Central Mountains. Isolated showers should linger into Monday evening over Southern PA associated with the warm front working into the area. However, the associated shortwave and best forcing should pass by late Monday night, so expect rain-free conditions heading into Tuesday morning. Surging low level moisture and a light southerly breeze should result in much warmer conditions Monday night than recent nights with min temps in the 65-70F range in most spots. The warm front is progged to lift north of the region Tuesday. However, surging PWATs ahead of another upstream shortwave over the Grt Lks should support plenty of cloud cover and widespread convection by afternoon, which will hold temps down somewhat. Highs on Tuesday will likely be 5 to 10 degrees cooler than Monday, but will end up right around average for this time of year. Weak mid level flow and deep layer shear indicates the threat of severe weather is low. Latest ensemble plumes indicate aerial average rainfall of 0.2 to 0.4 inches is most likely, with locally higher amounts from any tsra. Shower and thunderstorm chances will remain in the forecast through midweek as an upper level trough is progged to pass overhead on Wednesday. Higher PWATs will be lingering from Tuesday`s system as we remain in the warm sector post warm front. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... Building high pressure over the western and central US will bring an increasing threat for excessive heat and uncomfortable humidity as the calendar flips from July to August. Current ensemble members show us settling into a ring of fire pattern towards the end of this week. Diurnally driven convection is likely each afternoon through the end of the week. The ridging out west is likely to stay firmly in place through the course of this weekend. Long range guidance suggests the next frontal system will slide across the Commonwealth Saturday evening as an upper level trough dips across the great lakes and into the northern Ohio Valley. More widespread showers and thunderstorms are possible with this system as it will be more than just diurnally driven. && .AVIATION /03Z MONDAY THROUGH FRIDAY/... There is high (> 90%) confidence in VFR conditions continuing through 18Z Monday as central Pennsylvania remains under the influence of surface high pressure. Localized FEW/SCT clouds along the higher elevations remain possible through 22Z Sunday before SKC conditions prevail overnight. Fog formation remains plausible across the northern tier and have kept with persistence based on similar environmental set-up as the previous two nights with RAP model soundings and HREF probabilities of MVFR/IFR visibilities decreasing at BFD and IPT since the previous TAF package. Outlook... Tue-Wed...Increasing Chcs for SHRA/TSRA. Restrictions possible. Thu-Fri...PM SHRA/TSRA with localized restrictions possible. && .CLIMATE... A record high temperature of 87 degrees was set at Bradford today. This ties the old record of 87 degree set in 2023. The average temperature from January 1 to July 27, 2024 at Harrisburg was 56.4F, which is the warmest year-to-date on record. && .CTP WATCHES/WARNINGS/ADVISORIES... None. && $$ SYNOPSIS...DeVoir/Fitzgerald NEAR TERM...DeVoir/Fitzgerald/Banghoff SHORT TERM...DeVoir/Fitzgerald/Banghoff LONG TERM...Bowen AVIATION...DeVoir/NPB CLIMATE...Evans
Area Forecast Discussion
National Weather Service Dodge City KS
1101 PM CDT Sun Jul 28 2024 .KEY MESSAGES... - Isolated to widely scattered thunderstorms (15-25%) early this evening along the I-70 corridor and also possibly (15% or less) in extreme southwest Kansas. Main hazard will be wind gusts of 60 to 70 mph. - Monday through Wednesday high temperatures will range from 102 and 106. Heat index near 105 possible each day, mainly east of highway 183. - Monday through Thursday an excessive heat warning is in effect for Stafford, Pratt and Barber counties. Heat index of 105 to 110 possible along and east of highway 281. && .DISCUSSION... Issued at 234 PM CDT Sun Jul 28 2024 Earlier this morning, a 500mb high was located near El Paso, with upper waves evident across the Central Rockies and Four Corners region. These waves were located on the northern edge of this 500mb high and near a 300mb jet streak. CAMS are in good agreement today, taking these upper level waves east northeast into northern Kansas and Nebraska by late day, which will give rise to scattered afternoon thunderstorms. What storms that do develop may even be severe given the forecast 0-6km shear, cooler mid level temperatures (weak/no CIN), and the location of a surface boundary ahead of the approaching upper level trough, mainly north of the I-70 corridor. Further south, the shear and flow aloft will be weaker as +16C 700mb temperatures spread eastward into extreme southwest Kansas. These conditions will limit the chance for late day/evening storms further south, but at this time am unable to rule out an isolated evening thunderstorm or two north of a Garden City to Ness City to La Crosse line based on the locations of a surface boundary and given that we did have a few elevated thunderstorms earlier today despite these warm mid level temperatures. The chance for any storm to develop near or south of the I-70 corridor currently appears small (<20%). However, if a storm does develop, it will be capable of producing wind gusts of 60 to 70 mph and hail up to quarters. Another area to monitor this evening is across extreme southwest Kansas (Morton county area). Satellite already has afternoon cu developing west of this area and the latest HRRR does have isolated convection developing in this area where a surface boundary is currently located. As we look ahead to the upcoming work week...Ensemble clusters today were similar to previous runs moving the 500mb high east into Texas through midweek and then retrograding this upper high westward towards the Four Corners region late in the week. This trend, which all the ensemble clusters have been advertising for the last several days, will result in a period of extreme heat early in the week, followed by improving chances for thunderstorms mid to late week as the upper ridge weakens and begins to move westward in response to multiple upper waves crossing the Central Plains. For Monday and Tuesday, as the 500mb high builds east into Texas, a period of hot and dry conditions can be expected across southwest Kansas. NBM guidance has not changed much over the past several days regarding the forecast highs, and also little spread in the 10th to 90th percentile have been observed. Ensembles have remained consistent over the past several runs in the forecast of the 850-700mb temperatures during the same timeframe. Given all this, it should be no surprise that the ECMWF Extreme Forecast Index and Shift of Tails have also been very consistent in indicating high confidence in an extreme temperature event. As a result, there is a +80% chance that temperatures will be 102F or greater during the first half of the work week, with afternoon heat index values near 105F possible. With this high confidence on the temperature forecast on Monday along with good collaboration will go ahead an issue a heat advisory for areas where heat index values are currently forecast to be 105 or greater. Along and east of highway 281 this heat will linger into Thursday and given the length of time this area with have afternoon heat index readings of 105 to 110 plus night time temperatures only falling into the mid to upper 70s will upgrade the excessive heat watch to an excessive heat warning. Late Wednesday, all the ensemble clusters are in good agreement that a more significant upper level trough will cross the Rockies and move out into the Central Plains. This will not only weaken the upper high over Kansas and Oklahoma but also allow a weak cold front to move south out of Nebraska and into Kansas Wednesday night/early Thursday. The timing of this cold front is the biggest discrepancy between the ensembles today, but despite these differences, they are all trending in the same direction with some cooler air returning. This upcoming cool down will not be significant based on the latest ensemble mean 850mb temperature trends, but it will replace highs in the triple digits early in the week with highs in the mid to upper 90s in the latter half of the work week. Additionally, with the upper high retrograding westward, it will allow for a northwest flow to develop over eastern Colorado and western Kansas. This will favor ongoing chances for thunderstorms across southwest Kansas through the end of the week and possibly into early next weekend. && .AVIATION /06Z TAFS THROUGH 06Z TUESDAY/... Issued at 1111 PM CDT Sun Jul 28 2024 VFR expected through TAF pd. SE/S winds will increase 10-20 kt during the daylight hours in association with diurnal mechanical mixing of winds. Winds will abate 5-15 kt by dusk. && .DDC WATCHES/WARNINGS/ADVISORIES... Heat Advisory from noon to 8 PM CDT Monday for KSZ031-046-065- 079-080-088-089. Excessive Heat Warning from noon Monday to 8 PM CDT Thursday for KSZ066-081-090. && $$ DISCUSSION...Burgert AVIATION...Sugden
Forecast Discussion at weather.gov/mqt.

&& .DLH WATCHES/WARNINGS/ADVISORIES... MN...None. WI...None. MARINE...None. && $$ DISCUSSION...Melde AVIATION...NLy MARINE...Melde
Area Forecast Discussion
National Weather Service Des Moines IA
206 PM CDT Sun Jul 28 2024 .KEY MESSAGES... - Strong to severe storm possible this afternoon into tonight - main hazard is damaging wind gusts, but hail, a tornado or two, and locally heavy rainfall are secondary hazards. - Heat Advisory for southwest into part of south central Iowa Monday afternoon/early evening as heat and humidity push heat index values near/above 105 degrees. More widespread heat headlines probable Tuesday and Wednesday. - Occasional storm chances with low predictability of timing, location, and severity generally between Tuesday and late week. && .DISCUSSION... Issued at 207 PM CDT Sun Jul 28 2024 Midday GOES-East upper level water vapor imagery shows the mid-level shortwave trough that is departing the state with a plume of Gulf moisture preceding it. Back to the west and entering Iowa is the leftovers of an MCV that tracked across Nebraska and this feature results in the biggest change to the forecast in the near term. New TCU development has recently occurred near and west of Sioux City with storms slowly blossoming in this area. Latest convective allowing models (CAMs) are not handling the current picture well and lends itself to lowered confidence. Many CAMs with the exception of recent HRRR runs show storms maintaining or developing as they move into western Iowa. How much they intensify into western and our central Iowa forecast area remains uncertain as warmer air moves in aloft that may set up a cap, though this may be just behind the MCV and storms. 1 minute GOES-East Day Cloud Phase RGB is showing perhaps what may be a north-south line of more agitated and clumping cumulus nearing the Missouri River and perhaps what the CAMs are depicting. Ahead of the MCV, latest SPC mesoanalysis shows 2000-2500 J/kg uncapped of surface based CAPE (SBCAPE). HRRR soundings at CRL and CSQ show entrainment CAPE +/-200 J/kg either side of 1000 J/kg so quite a bit less than the RAP SBCAPE. These HRRR soundings do depict strong low and moderate mid-level lapse rates along with quite a bit of dry sub-cloud air that yield downdraft CAPE values between 750-1000 J/kg. Effective shear, particularly higher values of it, will be arriving with or behind the MCV/storms. So, damaging wind gusts appear to be the main hazard. Hail cannot be ruled out given lapse rates, but the freezing level is around 14-15kft with 1" hail heights around 35kft+ that may limit the hail hazard. A tornado or two is possible, but will need to locally back winds and/or increase flow above the surface to elongate the hodographs and provide better ingest of streamwise vorticity. This round of storms will track across a portion of central Iowa through the evening. Their intensity with eastern extent into central Iowa will likely weaken, but until then some severe risk may exist over western into perhaps central Iowa. Right on the heels of the MCV will be the shortwave trough that can be seen in the GOES imagery over the Dakotas. As this forcing approaches the state, low level warm air advection will be another forcing mechanism. This should result in storms dropping into the state from the northwest around or after midnight, though CAMs are split in this evolution. The other forcing will be a strengthening low level jet, though compared to yesterday it is not as far north and angled less into the state. However, this should kick off storms in advance of the southeastward dropping storms toward midnight. While surface based storms are unlikely given the warm wedge aloft, MUCAPE values around 750J/kg are likely with better deep layer shear. If storms do exists, particularly with the southeastward moving storms, then borderline severe hail and gusty winds may be possible. On the heavy rainfall side, the parameter space is favorable for efficient rainfall both tonight as well as this afternoon. Flash flood guidance shows 6 hour values of at least 2.5 if not 3 inches while 3 hour values are at 2 inches. Forecast QPF totals from a variety of deterministic models show isolated pockets of 3 inches with a few showing storm tracks of 1.5 to 3". 00z HREF localized probability matched mean (LPMM) shows similar with areas of 2" with isolated, sub county sized 3" embedded bullseye while the 12z HREF LPMM is slightly more concerning with a 5"+ bullseye south of the Des Moines metro, but overall less coverage of heavy rainfall. WPC initially had a slight risk of excessive rainfall over much of our area. This seemed a bit aggressive at the time given that our antecedent conditions have improved with soil moisture capacity ranging from 50-60% saturated over northern Iowa to 25-50% over central and southern Iowa and USGS streamflows are at normal or above normal percentiles on area waterways (versus much above or high as was the case earlier in July). Thus, was able to coordinate with WPC on removing slight and maintaining the marginal, which seems reasonable given that if the rain fell fast enough over an urbanized area, a flash flood could occur. All of the storm activity will depart the area by around or shortly after sunrise across our forecast area. Then, the mid-level ridge will build back over the region through at least Wednesday, but not too far poleward with Iowa residing on the northern periphery. Thus, it will certainly be a hot and humid period, particularly over southern Iowa. Monday will see heat index values near or top 105 degrees over southwest Iowa. Tuesday and Wednesday look to have more widespread heat index values over 105 degrees to around 110 degrees over southern to around Highway 30 or at least I-80. Examining the experimental HeatRisk, it does bring level 2/orange/moderate into southern and parts of central Iowa on Monday and then level 3/red/major into southern Iowa Tuesday and more of southern into parts of central Iowa on Wednesday. So, this brings us to a headline decision. We debated doing a prolonged advisory through Wednesday given the heat index values across the south. However, there is a small reprieve Monday night with lows to around 70 degrees and heat index values below 75. Then, Tuesday and Wednesday heat index values in the south are 105+ to around 110 degrees with no overnight reprieve. Thus, we may need a two day warning there with an advisory somewhere north of that into central Iowa. Avoiding the confusion of a double headline (advisory Monday, watch Tuesday/Wednesday), attempting to keep headlines as simple as possible, and trying to coordinate as best as possible with neighboring offices, we will be issuing a heat advisory over a part of our southwestern forecast area Iowa for Monday afternoon/early evening. Now, there are two failure modes for the upcoming heat headlines. One is the high level western US wildfire smoke that will be moving overhead. This may lower temperatures a few degrees at most and thus result in heat index values below criteria. The second is with our proximity to the top of the ridge as there will be multiple low amplitude shortwaves riding overtop of it. This will bring occasional storm chances Monday night through at least Wednesday. Much of the guidance does not show anything Monday night and our forecast is currently showing less than 15% PoPs, but the 12z NAM has an MCS barreling southeast through Iowa from South Dakota while the 0z ECMWF has one dropping through eastern Iowa out of eastern Minnesota/Wisconsin. There is a more amplified shortwave trough approaching the area later Wednesday or Thursday. The GFS continues to advertise a much faster speed versus the slower CMC and ECMWF. 0z cluster analysis does not provide much in the way of weighting towards one solution or another so will stay the course with initial National Blend of Models. Thus, the higher chances for storms will probably be Tuesday night through Wednesday night or Thursday depending on timing. Colorado State University`s machine learning random forest outlook highlights this period (their day 3 and 4) with 15% severe probabilities. SPC highlights Tuesday night in their day 3 outlook as well, but stresses the uncertainty and that this is more of a pattern recognition assigned risk. With mesoscale details lacking at this point, will need to monitor severe potential in the upcoming days. Whenever the more amplified shortwave does pass, it will push down the ridge and bring an end of the high heat with highs back into mainly the 80s. && .AVIATION /18Z TAFS THROUGH 18Z MONDAY/... Issued at 1247 PM CDT Sun Jul 28 2024 VFR conditions prevail with cumulus popping around FL015 to FL020 early this afternoon. Biggest change in this cycle is that storms are now expected to move into the central part of the state later this afternoon into early this evening over southern and some portion of central Iowa. As these move out, another round may arrive from the northwest, but there is quite a bit of uncertainty in how storm potential may play out. So have removed TS mention over northern sites later tonight and have left prolonged SHRA trying to maintain some continuity given the uncertainty. Lowered ceilings are possible over northern Iowa Monday morning that may bring ceiling restrictions for a part of the morning. && .DMX WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...Ansorge AVIATION...Ansorge
Area Forecast Discussion
National Weather Service Detroit/Pontiac MI
1203 AM EDT Mon Jul 29 2024 .KEY MESSAGES... - Very warm and humid conditions will prevail through the upcoming week. - A stray shower remains possible late tonight, and there is also a chance of showers and thunderstorms Monday and Tuesday, with locally heavy rain possible. Mostly dry Wednesday with thunderstorm chances returning Wednesday Night/Thursday. && .AVIATION... A band of mid to high level clouds with a few sprinkles during the evening are the first signs of moisture and instability returning ahead of Plains low pressure. The 00Z DTX soundings shows a formidable layer of dry air that held back the evening showers but which is forecast to moisten considerably during the late night. This process could result spotty showers spreading back into SE Mi within the thickening mid cloud pattern. Diurnally disrupted MVFR clouds across the Ohio valley into into northern IL also expand into Lower Mi by early morning in a warm frontal fashion signaled also by surface Td rising toward 70 F. This low level moisture fuels or sustains from the west additional showers with a thunderstorm also possible during peak afternoon instability. For DTW/D21 Convection... Isolated thunderstorms are possible across D21 and at DTW in the afternoon and Monday evening. A PROB30 is maintained in this forecast update to account for this, but timing may last longer into Monday evening. DTW THRESHOLD PROBABILITIES... * Low to medium for thunderstorms Monday from 20-24Z. * Medium for ceilings at or below 5000 ft in the morning and during late day convection. && .PREV DISCUSSION... Issued at 357 PM EDT Sun Jul 28 2024 DISCUSSION... Weather will remain dry the rest of today under mostly clear skies while daytime mixing heights have aided in daytime highs climbing well into the 80s this afternoon. Influence of the high pressure will relent this evening into tomorrow as a negatively tilted mid level trough lifts out of the Mid-Mississippi Valley. Southerly flow ahead of this trough will start to draw in more tropical air into Michigan early tonight. Weak ascent within the theta-e plume tonight supports at least some low PoPs during the overnight, but better chances tonight should hold to the southwest. The dry airmass noted on the 12Z DTX RAOB this morning will give way to deeper moisture by early tomorrow morning as the main trough axis reaches southern Lake Michigan. A hot and humid day will be in store with daytime highs back into the low/mid 80s and dewpoints climbing to around 70 degrees. PWATs are expected to improve towards to 1.8 inches or greater. Daytime instability will also improve by tomorrow afternoon with the RAP offering 500-1000 J/kg of MLCAPE, which will support scattered showers and thunderstorms. Weak shear and weak mid- level lapse rates will limit potential for organized or severe thunderstorms. However, the moderate instability and steep low level lapse rates will support some potential for isolated strong water loaded downburst winds. The high moisture will also allow for isolated heavy rainfall. Will carry PoPs into Monday night, but it will be possible that activity could be fairly isolated as nocturnal instability develops. The potential for a shortwave lifting into Michigan along with continued deep moisture will be the main reason for maintaining PoPs at this time. Tuesday will be similar, if not slightly better compared to Monday, in terms of shear and steep mid-level lapse rates. Instability looks to be slightly greater as another inbound shortwave arrives within the northwest flow aloft. Organized thunderstorm activity will again be limited, but isolated strong downburst winds and heavy rain will be possible Tuesday as well. Brief period of mostly dry conditions during the day Wednesday as a surface high pressure and shortwave ridge pass through. Hot and humid conditions are expected to continue through mid week with Wednesday pushing towards 90 degrees and dewpoints possibly into the 70s. The next mid/upper level trough moves into the western Great Lakes on Thursday with good diffluence aloft, improved shear and mid- level lapse rates, and moderate instability. This set up would be more supportive of organized thunderstorms across southeast Michigan. Still time to hash out better details as we approach mid- week. MARINE... Influence of high pressure quickly wanes this evening as a shortwave currently residing over the northern Ohio Valley/western Great Lakes advances towards the central lakes. Associated scattered shower and storm chances are initially confined to the southern Great Lakes and Saginaw Bay late tonight-early Monday before expanding over the remainder of the region latter half of Monday through Tuesday with the arrival of a second system over Lake Superior. This secondary system drives a weak cold front across the area Tuesday night bringing a brief break in storm chances. Active pattern is then reestablished by late Wednesday and looks to continue through the late week period as another Plains low slowly tracks over the Great Lakes. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...None. Lake Huron...None. Lake St Clair...None. Michigan waters of Lake Erie...None. && $$ AVIATION.....BT DISCUSSION...AA MARINE.......KDK You can obtain your latest National Weather Service forecasts online at www.weather.gov/detroit.
Area Forecast Discussion
National Weather Service El Paso Tx/Santa Teresa NM
540 PM MDT Sun Jul 28 2024 ...New AVIATION... .SYNOPSIS... Issued at 227 PM MDT Sun Jul 28 2024 Shower and storm chances continue through the beginning of this next week, favoring the mountains and areas along and west of the Continental Divide. Localized flash flooding and gusty outflow winds will be the primary threats. Mostly dry and abnormally warm conditions continue for the Rio Grande Valley and western Texas through the week. && .DISCUSSION... Issued at 227 PM MDT Sun Jul 28 2024 Overall, no major changes in the forecast from previous forecast packages with daily afternoon/evening shower and thunderstorm chances, focusing over area along and west of the Continental Divide and the Gila region. Current water vapor satellite imagery overlayed with 500mb RAP analysis shows high pressure aloft directly over southern NM and west TX. At the surface, highest PW values of 1.0-1.3 inches generally occur areas along the International Border and southwestern NM, along with dew points in the upper 50s to low 60s. PW values of less than 1.0 inch for areas north of the I-10 corridor. This sufficient amount of moisture is locked in under the aforementioned high pressure aloft. With very little shear and sufficient instability, typical monsoon-like showers and thunderstorms can be expected this afternoon and evening. Focusing over the mountains and areas closer to the AZ border. Orographically influences will get convection started over the mountains before transitioning to outflow dominated development during the late afternoon and evening over the lowlands. Coverage across the lowlands, especially areas along and east of the RGV will be isolated. Like previous days, the primary threats will be gusty outflow winds and localized flash flooding. High temperatures this afternoon will top out in the upper 90s and low 100s across the lowlands. Upper high and ridge axis will shift further east across central and eastern TX at the beginning of the week. The corresponding monsoonal moisture corridor will respond, slowly shifting east across NM. Fairly consistent weather pattern will setup with daily afternoon and evening shower and thunderstorm chances areawide, scattered in the mountains and isolated in the lowlands. High temperatures through the first half of the week will be in the upper 90s to low 100s across the lowlands, 100-103 for the El Paso metro. By the end of next work week and into the weekend. Model and ensemble guidance shows the upper level high reestablishing itself of the Central Rockies. Above average warmth, along with general monsoonal type storm activity can be expected. && .AVIATION... (00Z TAFS) Issued at 533 PM MDT Sun Jul 28 2024 VFR conditions expected to prevalent through the period with KDMN having a brief of period of TSRA and possible MVFR from 00Z to 03Z. Afterwards as thunderstorms diminish, all taf sites should be VFR with sct- broken ceilings at 120-200 kft. Thunderstorms will redevelop after 18Z tomorrow with scattered storms over the mountains and ioslated storms possible over the lowlands. Surface winds not near thunderstorms will be generally northwest at 7 to 10 knots with occasional gusts to 20 knots through the period. && .FIRE WEATHER... Issued at 227 PM MDT Sun Jul 28 2024 Fire weather concerns remain LOW through the period. Recent monsoonal moisture surges and rainfall have helped, as ERC values below 50th percentile at most sites. Weather wise, scattered shower and storm chances remain in the forecast for the remainder of today and into next week, with the focus and better coverage for areas along and west of the Divide and Gila Region. Gusty outflow winds, lightning, and wetting rains will be the primary impacts. Temperatures through the period will continue running above the seasonal average with Min RH values each in the 20-40 percent range of the high terrain and 17-30 percent range over the lowlands. Winds will be light and generally diurnal/terrain driven in terms of direction. && .PRELIMINARY POINT TEMPS/POPS... El Paso 77 101 79 103 / 40 10 30 10 Sierra Blanca 69 94 69 95 / 30 20 20 20 Las Cruces 73 101 74 101 / 40 10 30 10 Alamogordo 70 99 71 100 / 20 10 20 10 Cloudcroft 54 76 55 77 / 20 40 20 40 Truth or Consequences 71 97 72 96 / 20 20 20 20 Silver City 64 90 64 90 / 50 60 40 60 Deming 71 99 71 99 / 40 20 40 10 Lordsburg 69 95 69 96 / 40 50 50 40 West El Paso Metro 76 99 76 100 / 40 10 30 10 Dell City 71 101 72 102 / 20 10 10 10 Fort Hancock 72 101 73 101 / 40 20 30 20 Loma Linda 69 92 70 93 / 30 20 20 10 Fabens 74 100 74 100 / 40 10 20 10 Santa Teresa 73 98 74 98 / 50 10 40 10 White Sands HQ 74 100 75 99 / 40 20 30 20 Jornada Range 71 99 71 98 / 40 20 30 20 Hatch 71 101 71 101 / 40 20 30 20 Columbus 73 98 73 98 / 50 20 50 10 Orogrande 71 98 71 98 / 30 10 20 10 Mayhill 60 88 59 88 / 20 30 10 30 Mescalero 59 87 59 87 / 20 40 20 40 Timberon 58 86 58 87 / 20 30 20 30 Winston 59 88 59 87 / 30 50 20 50 Hillsboro 67 95 68 95 / 40 40 40 30 Spaceport 68 98 69 98 / 30 20 20 20 Lake Roberts 59 90 60 89 / 50 70 40 70 Hurley 65 94 66 93 / 40 50 30 40 Cliff 64 100 66 100 / 50 60 30 50 Mule Creek 66 92 66 92 / 40 60 40 50 Faywood 66 93 67 93 / 40 40 40 40 Animas 69 95 69 96 / 50 50 60 40 Hachita 69 95 68 95 / 40 40 60 30 Antelope Wells 67 94 66 94 / 60 60 70 50 Cloverdale 64 88 64 89 / 60 70 70 50 && .EPZ WATCHES/WARNINGS/ADVISORIES... TX...None. NM...None. && $$ FORECASTER...04-Lundeen
Area Forecast Discussion
National Weather Service Sioux Falls SD
1046 PM CDT Sun Jul 28 2024 .KEY MESSAGES... - Scattered strong to severe storms this evening. Greatest threat is from 7-8 PM to 1 AM with potential for hail up to hen egg size with initial activity, wind gusts exceeding 70 mph, and a few tornadoes. Locally heavy downpours may bring 2+ inches of rain to a few locations as well. Beyond tonight, nightly low storm chances continue for portions of the region through Wednesday night. - Hot and humid conditions continue through the week. The highest humidity comes Tuesday and Wednesday, when afternoon heat index readings near or over 100 degrees are most likely. - Wildfire smoke aloft will return late tonight-Monday, but confidence in surface impacts is low. Those who are highly sensitive to air pollution should monitor air quality conditions and adjust outdoor plans accordingly. && .DISCUSSION... Issued at 256 PM CDT Sun Jul 28 2024 THIS AFTERNOON-TONIGHT: Looking at a couple of areas for convection through the rest of this afternoon and tonight. First will be across mainly northwest Iowa, as a compact wave/MCV remnants pushes east across eastern Nebraska/western Iowa. This activity is moving into an airmass characterized by moderate instability (1500-2000J/kg) and increasing deep layer shear per the latest RAP projections. While greater coverage of this activity is expected to be south of Highway 20, will have to monitor our far southeast counties for an isolated strong to severe storm over the next few hours until this wave moves east of the area. Stronger mid-level wave is moving across western South Dakota early this afternoon and will continue to track east across the eastern Dakotas into Minnesota through the evening/overnight. Already seeing spotty storms develop along the associated surface boundary which extends from western SD into southeast ND. Instability has been limited in some areas due to morning showers/clouds across our western counties, but that activity continues to wane, and partial clearing should allow stronger heating to push MLCAPE values near 2000J/kg ahead of this activity early this evening. Shear starts off on the weak side this afternoon, but the approaching wave will bring increasing mid-level winds, with shear increasing accordingly. This will support organized storms with a threat of large hail with the initial development. This would be more likely west of our forecast area, or perhaps just into our northwest corner early this evening. Storms continue to grow upscale as they progress east this evening, with the primary threat transitioning to strong/damaging winds, possibly in excess of 70-75 mph. Exact location of the greatest threat is still somewhat uncertain, though the high-res models from this morning are showing better consensus today than at this time yesterday. This leads to slightly higher confidence that the main impacts for our forecast area will be near and north of the I-90 corridor, though there is a low-moderate (30-50%) probability of stronger storms extending south of I-90 toward the Missouri River after dark. While the primary threats tonight are large hail and damaging winds, there is a non-zero threat of tornadoes, especially if bowing segments can become established, as 0-3km shear vectors would be oriented nearly perpendicular to the lines. In addition to the aforementioned severe threat, we will have to monitor for locally heavy rainfall as well. Airmass is primed as has already been seen with the activity around Sioux City, with Wayne Nebraska AWOS (KLCG) reporting nearly an inch of rain in 20 minutes. Precipitable water values exceeding 1.5-1.75 inches are above the 90th percentile of climatology, and while storms will become increasingly progressive through this evening, any storms which are slower moving or impact urban areas could present a localized flash flood threat. MONDAY-THURSDAY: Tonight`s storms should exit to the east of our forecast area by daybreak Monday and the daytime hours should remain rain-free. However, some areas could start the day off with some patchy fog/stratus in the wake of departing storms. Temperatures may also be impacted by a return of smoke aloft from western wildfires, but still looks to be a warm day with highs in the mid 80s to lower 90s. Dew points in the mid 60s-lower 70s will push heat indices into the 90s in many areas, but at this time it looks to remain shy of advisory criteria. Speaking of the wildfire smoke, low probability that we could see some surface impacts on Monday as winds turn to the northwest behind the departing storms. HRRR Smoke model does show some increase in near surface smoke, but low confidence in whether there will be enough to push air quality into a higher level than Moderate/yellow or reduce visibility. Tuesday-Wednesday continue to look like the hottest and most humid days of the week and this would be the period of greater concern for heat headlines. Barring lingering impacts from isolated-scattered nighttime storms, trends continue to support highs both days in the upper 80s to mid 90s, with dew points in the lower-mid 70s, perhaps upper 70s in a few locations. These values support heat indices topping 100 in some areas both afternoons, mainly south of I-90. Various waves sliding across the region in quasi-zonal flow could bring periodic storm chances, mainly focused during the evening to overnight hours Monday night through Wednesday night. Strongest of these waves appears to be Wednesday night and will carry higher and more widespread chance pops during that period. However, details in exact timing and location of storms are far from certain. That said, cannot rule out a few strong to severe storms given unstable mid level lapse rates and areas of moderate to strong shear. FRIDAY-SUNDAY: Stronger mid-upper level ridge builds again over the western CONUS, placing us back in west-northwest flow aloft by this weekend. This may allow temperatures to ease slightly, though humid conditions look to continue. Confidence in precipitation chances is low as any weak waves in the northwest flow could trigger spotty showers or storms. Unfortunately, this flow pattern aloft will likely maintain our hazy/smoky skies as we move through the first weekend in August. && .AVIATION /06Z TAFS THROUGH 06Z TUESDAY/... Issued at 1045 PM CDT Sun Jul 28 2024 Outside of a few isolated showers along/north of the MO River Valley, latest radar imagery shows largely quiet conditions across our area. Given how storms have panned out this evening, think any additional development overnight would remain isolated in nature. Otherwise, expect light and variable winds to continue for much of the period. This in combination with a decent amount of moisture in the lower levels may result in fog prior to/around daybreak. Thus, could see cigs/vsbys briefly fall to MVFR levels. Any fog development should burn off quickly though, allowing dry conditions and mostly sunny skies to prevail Monday. && .FSD WATCHES/WARNINGS/ADVISORIES... SD...None. MN...None. IA...None. NE...None. && $$ DISCUSSION...JH AVIATION...SST
Area Forecast Discussion
National Weather Service Glasgow MT
204 PM MDT Sun Jul 28 2024 .DISCUSSION... KEY MESSAGES: - More noticeable push of smoke and haze from wildfires across the Western US will begin moving into the region today. - Next best chance of rainfall is today, though chances for even a simple hundredth of accumulation still remain generally under >40% for most areas. Wetting rain chances are near 0%. - Fire Weather Watch for Monday is being upgraded to a Red Flag Warning this afternoon. WEATHER PATTERN OVERVIEW: A shortwave moving along the upper-level trough draped across the western US will bring chances for non-wetting rain for northeast Montana. SPC currently keeps most of northeast Montana in a general thunderstorm risk, though the Marginal risk for convection was expanded across southeast Montana, with fringes of this risk area in Prairie County. Greatest risk, as has been with the relatively-drier low-level and limited PWATS, is winds as high as 60 mph. Limiting factor will be any smoke that moves into the area, inhibiting surface heating and reducing overall instability. Given that locations will see an increase in RH values, given the close proximity to sunset, decided to delay the start of the previously issued Fire Weather Watch from this afternoon to Monday 10 AM MDT. Confidence that the greatest fire risk will fall on Monday, with westerly winds increasing as RH values dip as low as 10%. Montana remains in a slight southwesterly/zonal flow through Tuesday night, at which point, another shortwave moves through. Given that PWATS will be similar to today`s rainfall chances, similar non-wetting rain can be expected. From Wednesday, upper level ridging remains the name of the game through the long-range forecast. FORECAST CONFIDENCE & DEVIATIONS: Felt confident with what the NBM output for PoP through the next 24 hrs. So no deviations were made. Western wildfires and southwesterly flow will bring in a more noticeable area of haze and smoke across northeast Montana. The Canadian Firework (smoke) model, along with the HRRR and RAP13, show this push today and extending into Monday. -Enriquez && .AVIATION... UPDATED: 1930Z FLIGHT CAT: VFR DISCUSSION: SMOKE and HAZE from western US wildfires begin to make a more noticeable move across eastern Montana. This may result in brief periods of near 6 SM visibility. Rain chances move through the region throughout the day, briefly bringing reduced visibility in stronger showers/thunderstorms SFC WIND: Light and variable. Winds shifting to more southerly winds this evening, generally under 10 kts. Becoming SW Monday after sunup. Erratic strong gusts will be possible near any thunderstorm this afternoon and evening especially near KGDV from 21 to 04Z. EQUIPMENT: With the KSDY observation sensor being down, have placed AMD NOT SKED in until it comes back. -Enriquez/GAH && .GGW WATCHES/WARNINGS/ADVISORIES... Red Flag Warning from 10 AM to 9 PM MDT Monday for Northern Valley and Northern Phillips Counties-The Little Rockies-The Lower Missouri River Breaks including the Charles M Russell National Wildlife Refuge. && $$ weather.gov/glasgow
Area Forecast Discussion
National Weather Service Goodland KS
418 PM MDT Sun Jul 28 2024 .KEY MESSAGES... - An isolated severe storm is possible this afternoon, mainly along/north of I-70 in KS-NE between 3-8 PM MDT. Quarter to golf ball size hail and wind gusts up to 70 mph are the primary severe weather hazards. Confidence is low with regard to whether or not storms will develop. - Monday through Wednesday are forecast to see temperatures in the 100`s with heat index values also in the 100`s. Locales generally along and east of Highway 83 could see heat index values in the mid 100`s Tuesday and Wednesday. - Not as hot Thursday through Saturday with high temperatures generally in the upper 90s and lower 100`s. Chance for smoke to return to the area if wildfires are still ongoing. && .SHORT TERM /THROUGH TONIGHT/... Issued at 200 PM MDT Sun Jul 28 2024 Overview: Unidirectional /westerly/ flow aloft will prevail over the Tri-State area today.. downstream of an upper level low progressing ENE from western Montana to southern Saskatchewan.. and upstream of an upper level low progressing ENE-NE from Iowa to the Great Lakes. Current and recent runs of the HRRR and NAM NEST suggest that strong insolation will aid in the development of isolated convection in climatologically/ geographically favored locations in the lee of the Rockies (Cheyenne Ridge, Palmer Divide) by ~21Z this afternoon -- that said convection will intensify as it progresses east (via ~30 knot westerly steering flow) toward the CO-KS border ~22Z -- and that an isolated supercell will emerge from said activity, propagating southeastward along/near I-70 invof Goodland, Colby and Oakley before dissipating ~00Z. The HRRR and NAM NEST also suggest that an isolated right-mover may emerge from convection initiating along/near the Cheyenne Ridge ~23Z.. and that said right-mover will propagate southeastward into portions of southwest Nebraska prior to dissipating ~02Z. Given that convection allowing guidance tends to be less reliable in weak forcing regimes, confidence remains below average with regard to whether or not the aforementioned scenario(s) will materialize / play-out as indicated. Nevertheless, it must be said that.. recent trends in visible satellite (e.g. towering Cu in southern Washington/Yuma counties and along the I-80 corridor from Cheyenne WY to Sidney NE at 1930Z).. lend a fair amount of credibility to convective initiation as indicated by the HRRR/NAM NEST (timing and location, at least). Environmental conditions over the Tri- State area -- characterized by a pronounced elevated mixed layer (8.5-9.0 C/km H7-H5 lapse rates), modest high-based instability (~1000 J/kg mlcape), extreme (~2000 J/kg) DCAPE and ~40 knots of effective deep layer shear (~15-25 KFT AGL) -- are certainly supportive of isolated supercells.. *if* any updrafts can survive/overcome a considerable amount of dry air entrainment. With the above in mind, expect a conditional potential for an isolated supercell (or two) capable of producing damaging winds and large hail. && .LONG TERM /MONDAY THROUGH SUNDAY/... Issued at 1227 PM MDT Sun Jul 28 2024 This upcoming week through the weekend continues to be forecast to see hot temperatures and low chances for storms. Monday and Tuesday remain forecast to see the upper ridge amplify over the Plains. With this temperatures continue to be forecast in the 100s with mid to upper 100`s possible on Tuesday. The main concern/inhibitor is the smoke from wildfires. The smoke from all the wildfires continues to move across the CONUS and for us as kept temperatures a few degrees lower than their potential. While the upper pattern is forecast to try and keep the smoke from the area, tomorrow may still see enough that temperatures remain in the upper 90`s and low 100`s instead of the mid 100`s (as the 34-35C 850mb temps would suggest). With the ridge axis over the area, storms are unlikely both days. Wednesday & Thursday, a shortwave trough is forecast to move through the Northern Plains. While not necessarily associated with any cold air mass, the trough should push the hotter temperatures out of the area and allow for 90`s and low 100`s. The shortwave trough and associated surface low should provide some additional lift for storms, especially on Wednesday. Even with the forcing though, the overall dry pattern and weak flow look to keep storm chances around or lower than 30%. Going into the weekend, an upper trough/low are forecast to deepen over the Eastern CONUS while the ridge rebuilds over the Western/Central portions of the CONUS. This will lower the storm potential back to 10% or less each day. There is still a small hint that a trough could rotate around the larger low in Eastern Canada and push through the Plains, providing higher storm chances and slightly cooler temperatures. However, most ensemble and deterministic guidance is favoring the ridge dominating again. The main inhibitor to temperatures climbing back into the 100`s is the northerly flow that is forecast. This would be similar flow to what brought smoke into the area the past week. If this occurs, temperatures will likely remain in the 90`s. && .AVIATION /00Z TAFS THROUGH 00Z TUESDAY/... Issued at 418 PM MDT Sun Jul 28 2024 Both terminals will see mainly VFR conditions through the forecast period. There is a chance from 00z-03z Monday that 5-6sm with -TSRA. Winds for KGLD, east around 10-15kts through 03z-04z, then light/variable. If any storms move to impact the terminal from 00z-03z, then variable gusts 30-45kts are possible. Winds for KMCK, east around 10kts through 02z, then light/variable, then east again by 19z Monday. If any storms move to impact the terminal from 00z-02z, then variable gusts 20-35kts are possible. && .CLIMATE... Issued at 1200 PM MDT Sun Jul 28 2024 July 29 High Temperature Records (F): Goodland......104 in 1947 McCook........109 in 1947 Burlington....100 in 2012 Hill City.....108 in 1917 July 30 High Temperature Records (F): Goodland......106 in 1935 McCook........105 in 2002 Burlington....101 in 2012 Hill City.....109 in 1976 July 31 High Temperature Records (F): Goodland......105 in 2002 McCook........107 in 2002 Burlington....102 in 2002 Hill City.....113 in 1934 Goodland has the potential for 5 consecutive days of highs of 100+ degrees which would tie it for the 14th longest on record. Last time this happened was July of 2012. McCook is also currently forecasted at 5 consecutive days of 100+ degree temperatures which would tie it for 20th all time. However a few days of overachieving temperatures could put them in the top 6 all time. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...None. CO...None. NE...None. && $$ SHORT TERM...BV LONG TERM...KAK AVIATION...JN CLIMATE...Trigg
Area Forecast Discussion...Updated
National Weather Service Lincoln IL
840 PM CDT Sun Jul 28 2024 .KEY MESSAGES... - Daily chances for showers and thunderstorms continue through Friday, with MCS activity giving the potential for some severe storms late tonight into Monday morning, and again late Monday afternoon into Monday evening. There remains periodic risk of strong to severe storms from Tuesday through Thursday. - Hot and humid conditions prevail much of this work week over central and southeast IL. Heat indices approach 100 degrees over the Illinois River on Monday afternoon. Heat indices are forecast to reach 100 to 110 during the afternoon and early evening hours Tuesday through Thursday, with Wednesday likely being the hottest day. && .UPDATE... Issued at 840 PM CDT Sun Jul 28 2024 01z/8pm regional VAD wind profilers show an 850mb jet streak already strengthening to 40kt at MCI. NAM has consistently suggested a 40-50kt nocturnal jet oriented from Oklahoma northeastward to southern Iowa by 06z. As the jet cranks up, clusters of thunderstorms currently across central Iowa will organize into an MCS, then shift E/SE into central Illinois late tonight into early Monday morning. With precipitable water values increasing to 2.00-2.25, the storms will be efficient rain- producers and may cause localized flash flooding in a few spots. While the timing and track of the system is still somewhat in question, confidence is growing that high rainfall rates will occur...especially along/south of the I-74 corridor between 10z/5am and 14z/9am. Have therefore adjusted PoPs up considerably, going with a 90-100% chance of thunderstorms during that time frame. Given antecedent dry conditions, think much of the rain will soak in...so any flash flooding should be isolated and mainly confined to urban locations. Barnes && .DISCUSSION... Issued at 300 PM CDT Sun Jul 28 2024 Mid afternoon surface analysis shows 1022 mb high pressure over the Atlantic States with a broad southerly flow of very warm and moist air on back side of high pressure ridge over IL. Florida like weather prevailed over central/se IL this afternoon with temps in the low to mid 80s and tropical like dewpoints in the low to mid 70s. Heat indices were in the upper 80s to around 90F over CWA. Radar mosaic shows a band of convection along and just east of I-57 in eastern IL while a larger area of convection over eastern MO and approaching the IL border/MS river between St Louis and Quincy and tracking NE. This convection was forming in an unstable air mass with MU Capes 2-3k j/kg and ML Capes 1500-2500 j/kg (highest toward MS river valley of western/sw IL) and weak wind shear ahead of an upper level trof in eastern MO and mid MS river valley. Moist PW values of 1.4-1.9 inches and highest near the Wabash river valley where PW near 2 inches. So pockets of heavy rains with the stronger cells along with gusty winds. MCS likely to develop by overnight on nose of sw 35-50 kt 850 mb jet over southeast IA/northeast MO and into west central IL and track ESE across central IL between 2 am and 10 am Monday. SPC day 1 outlook has marginal risk of severe storms over west central IL west of a Galesburg to Jacksonville line primarily for damaging winds and this marginal risk may be extended further east with CAMs trending faster with this storm complex. Heavy rains also a threat with PW values rising above 2 inches over central IL overnight into Mon morning. Marginal risk of severe storms continues over rest of central IL during through mid morning Monday, then another possible MCS with more storms that could develop late Monday afternoon into Monday evening. Though less confidence with the 2nd MCS affects on our CWA with CAMs starting to back off on its convection Monday night over central/se IL. Highs Monday in the mid to upper 80s with dewpoints in the 70s giving afternoon heat indices in the mid to upper 90s. Heat indices will likely top 100F over MS river valley of west central and sw IL Monday afternoon. Some more convection could track se over parts of CWA on Tue afternoon into Tue night with a frontal boundary moving into central IL on Tue, with best chance in eastern IL and from I-74 north. Highs in the upper 80s and lower 90s Tue (lowest in east central IL where higher convection chances are) with dewpoints in the mid to upper 70s giving afternoon heat indices of 99-107F, highest in southeast IL and from Galesburg to Springfield west. These areas may eventually need heat advisory Tue afternoon and has already been issued for areas west and sw of our CWA Tue afternoon through early Wed evening. Think Wednesday will be our hottest day as upper level ridge builds into IL with 500 mb heights rising to 592-595 dm by Wed afternoon. ECMWF is showing MCS activity sliding se over central IL Wed afternoon while other models only have isolated convection around on Wed afternoon. For now we kept lower pops on Wed with 20-30% chance and highest from I-74 north. Highs 90-95F Wed with dewpoints in the mid to upper 70s and even around 80F possible with afternoon heat indices 105-112F. Will likely need a head advisory across much if not all of our CWA on Wed afternoon and early Wed evening. Forecast models dig a cutoff upper level low/trof into the upper MS river valley on Thu. This to drive a cold front se through central and se IL during Thu night and into southeast IL fri morning and bring another round of convection. Highs Thu near 90F northern CWA and mid 90s far southeast IL from highway 50 south with moist dewpoints in the mid to upper 70s still. Heat indices Thu afternoon could reach 100-110F, highest south of I-70 and heat advisory may be needed again especially southern CWA. Chances of showers/thunderstorms lingers on Friday with upper level trof/low near central/east central IL and front pushing se through southeast IL Friday morning. Highs Friday in the mid to upper 80s central IL and around 90F in southeast IL. Heat indices could still reach upper 90s to around 100F south of I-70 Fri afternoon. Have a slight chance of convection in eastern/se IL Fri evening, then quieter conditions expected for next week as high pressure settles into the Great Lakes region. Seasonable highs in the mid to upper 80s Sat/Sunday with dewpoints in the upper 60s/lower 70s, still muggy but not nearly as much as this work week. 07 && .AVIATION... (For the 00z TAFs through 00z Monday Evening) Issued at 643 PM CDT Sun Jul 28 2024 Widely scattered convection is on the decrease across central Illinois early this evening, although a stray shower cannot be ruled out at KPIA/KSPI/KCMI over the next couple of hours. After that, attention will turn to a cluster of thunderstorms expected to form on the nose of the nocturnal low-level jet across Iowa/Missouri after midnight. While there is still some timing uncertainty, confidence is growing that the storms will shift E/SE across the heart of central Illinois late tonight into early Monday morning. Based on the latest HRRR timing, have introduced thunder at KPIA by 11z...then further east to KCMI by 13z. The convection will pass to the east of the terminals by 16z, followed by a period of lingering MVFR ceilings through midday. Ceilings will scatter from west to east by early afternoon with mostly dry weather anticipated through 00z Tue. Barnes && .ILX WATCHES/WARNINGS/ADVISORIES... None. && $$
Area Forecast Discussion...UPDATED
National Weather Service Indianapolis IN
1055 PM EDT Sun Jul 28 2024 .KEY MESSAGES... - Chances for showers or a thunderstorm this evening and again on Monday. - Daily storm chances continue through Friday, damaging winds possible Monday/Tuesday - Heat indices near 100 Wednesday && .FORECAST UPDATE... Issued at 1055 PM EDT Sun Jul 28 2024 Quick update to revise precipitation probabilities. Upper trough axis will deamplify and shift northeast. This, coupled with decreasing instability should limit convective coverage the rest of the night. The downward trend of remnant convection should continue. Confidence continues to increase on upstream storms over Iowa consolidating and moving toward Indiana as an MCS tomorrow morning, within modest west-northwesterly flow on the back side of aforementioned trough. && .MESOSCALE UPDATE... Issued at 910 PM EDT Sun Jul 28 2024 Flooding is likely across portions of Indianapolis urban core, given impermeable surfaces and heavy rainfall rates from the convective cluster moving in now. Deep warm cloud layer and warm rain process is expected supporting 1-2 inch per hour rainfall rates. IND ASOS has 1/4th mile visibility due to the intensity of the rainfall. A predictive Flood Advisory was issued to convey the potential for minor road flooding over the next hour. All cells across central Indiana will have the potential for heavy rates. Where upshear growth and training occurs, flooding or flash flooding will be possible given the unusually moist environment. Corfidi upshear shows similar cell motion but much slower, hence training potential. Once cold pools become established as with the Marion County cluster, more east-northeast and faster forward propagation will occur. During this transition, we have noted 35-45 mph wind gusts. && .SHORT TERM (This evening through Monday)... Issued at 234 PM EDT Sun Jul 28 2024 Surface analysis early this afternoon shows a strong area of high pressure in place over the east coast. A broad area of low pressure was found over the high plains. This was allowing a southerly flow of warmer and more humid air into Central Indiana. Aloft water vapor showed a moderate negatively tilted upper trough over the middle Mississippi Valley. This was allowing for a tropical plume of moisture to stream ahead of the trough in KY and IN. Radar this afternoon shows an areas of showers over NE Indiana exiting from this plume. Clearer skies over IL have allowed daytime heating to result in shower and thunderstorm development. These storms look to be progressing northeast toward Central Indiana Dew points across the area remained quite moist, in the lower 70s. Tonight... Models suggest that the upper trough axis will push east of Indiana by late this evening. This, along with the loss of daytime heating will allow for an end for shower and storm chances during the overnight hours. However, through the evening, chances for showers and storms will continue to persist ahead of the trough axis. HRRR continues to show scattered showers and thunderstorms through the evening. Forecast soundings remain quite saturated through the evening with pwats approaching 1.90 inches. Thus will use high pops this evening, but will taper these to lesser values overnight. Indiana will remain within the warm and humid air mass as southerly flow persists overnight. As dew points remain in the lower 70s, a warm night will be expected with lows in the lower to middle 70s. Meanwhile, an MCS is expected to develop overnight over IA and MO.... Monday... Another active weather day is expected on Monday. By the morning, the models suggest that the upper flow will be more zonal. By 12Z, the HRRR suggests a thunderstorm complex over IL pushing toward Indiana. The GFS 310K Isentropic surface shows strong lift arriving ahead of this feature, with plenty of moisture available. Again, forecast soundings show a nearly saturated column with pwats still quite high, near 1.90 inches. Thus confidence will be high for another round of showers and thunderstorms as this wave is expect pass across Central Indiana through the morning hours. Forecast soundings by afternoon continue to suggest a favorable column for convection and as heating by late afternoon leads to CAPE values expected over 1500 J/KG. HRRR suggests addition thunderstorm development late in the afternoon. Thus pops will be needed throughout the day, due to two rounds of showers and storms. The first round in the morning due to MCS propagation and isentropic lift, and the second due to afternoon convection due to daytime heating. Highs should reach the middle to upper 80s. && .LONG TERM (Monday night through Sunday)... Issued at 234 PM EDT Sun Jul 28 2024 Monday Night Through Wednesday. A fairly active week is expected with multiple rounds of rain as ridge riding thunderstorms are expected to impact Indiana. The first threat for thunderstorms will be late Monday into Monday night with a weak shortwave pushing southeast from Iowa. While confidence in the complex is high, confidence is fairly low in the exact timing and whether this system impacts central Indiana or stays to the southwest. The next round looks to arrive late Tuesday night into early Wednesday, but details remain quite uncertain. Each successive wave will further drop the confidence as these systems will be heavily impacted by the mesoscale features of the previous rounds of storms and how they modify the environment. The severe threat is quite marginal with a combination of unfavorable diurnal timing and only marginal bulk shear of 10-20kts, but with a well established cold pool, pockets of strong to damaging winds can`t be ruled out. The threat for storms looks a bit lower for Wednesday as the ridge gradually progresses eastward, but diurnally driven afternoon convection will be possible. Near Heat Advisory level heat indexes look likely Wednesday afternoon with expected highs in the low 90s and dewpoints across south central Indiana in the mid to potentially upper 70s. This high heat would be dependent on a lack of cloud debris from Tuesday night convection, so confidence is still fairly low in dangerous heat levels. With the potential for multiple rounds of storms, will have to also keep an eye out for isolated flooding if successive systems impact the same areas. Thursday Through Sunday. There could be additional rounds of storms Thursday into Friday but this will all be dependent on how the mesoscale environment is impacted by the storms earlier in the week with low confidence on even the synoptic environment by Friday as models rapidly diverge. What does look likely is between Friday and Sunday, a more organized upper level low should drop southeast from Canada with impacts to the general Great Lakes Region. Quieter and slightly cooler weather then looks likely for the weekend as northwesterly flow becomes more dominant again. && .AVIATION (18Z TAF Issuance)... Issued at 234 PM EDT Sun Jul 28 2024 Impacts: - Mainly MVFR this period. - Scattered showers through early evening. Isolated thunderstorms possible. Discussion: An upper trough will be passing across Indiana and the TAF sites tonight. A tropical plume of moisture streaming north ahead of the trough and across Indiana will provide MVFR cigs across the TAF sites. HRRR suggests a few waves of showers and thunderstorms this afternoon, before coverage diminishes overnight. During the overnight hours the upper trough axis appears to shift to the east of Indiana and this may limit forcing. Thus due to low confidence for specific timing, VCSH has been used for much of the afternoon, with mainly a dry forecast overnight with MVFR CIGS. Time heights and forecast soundings continue to suggest nearly saturated lower levels. HRRR on Monday morning shows an area of thunderstorms arriving within the now westerly flow aloft. This will be the remnants of a decaying MCS, expected to arrive from MO and IA. For now, have used a VCTS mention during the morning hours until more confidence arrives for precise timing. && .IND WATCHES/WARNINGS/ADVISORIES... None. && $$ UPDATE...BRB SHORT TERM...Puma LONG TERM...White AVIATION...Puma
Area Forecast Discussion
National Weather Service Lake Charles LA
1039 PM CDT Sun Jul 28 2024 ...New UPDATE... .UPDATE... Issued at 1018 PM CDT Sun Jul 28 2024 The new pattern is here! Latest 500 mb RAP analysis places high pressure overtop the northeast GoM; its northwest fringe located just over the LCH CWA. This high pressure dome will remain in control, slowly creeping to the west over the next several days. Hot, humid conditions and very little rainfall can be expected. No updates were made to the forecast package tonight. 11/Calhoun && .SHORT TERM... (Tonight through Tuesday night) Issued at 256 PM CDT Sun Jul 28 2024 Scattered showers and thunderstorms have developed in the past hour across parts of SW and SC LA, with the activity moving north into parts of CENLA. This activity should weaken as we get into the evening hours and be dissipated by 9 to 10 pm. Expecting less convective coverage on Monday as the high pressure builds in our region. The best chances for rain will be along the I-10 corridor, with only a 20 to 30 percent chance. This will likely be a repeat for Tuesday afternoon. Temperature-wise, we warm up Monday, and expecting to reach the heat advisory thresholds of 108 F in parts of central Louisiana. Later shifts tonight will monitor to see if the heat advisory coverage area needs to be expanded further. && .LONG TERM... (Wednesday through next Saturday) Issued at 256 PM CDT Sun Jul 28 2024 The surface high pressure over the Gulf shifts west during the long term time frame, so the highest rain chances will be in the eastern Gulf states. Could see a need for heat advisories in some places during this time frame. && .AVIATION... (00Z TAFS) Issued at 608 PM CDT Sun Jul 28 2024 Mostly VFR conditions are expected through the period, however patchy lower ceilings may occur at KAEX around sunrise Monday. Winds will be light and south to southwest. && .PRELIMINARY POINT TEMPS/POPS... AEX 74 93 74 95 / 20 20 0 10 LCH 78 90 78 91 / 10 20 0 30 LFT 79 94 79 94 / 30 30 0 50 BPT 78 91 77 92 / 10 20 0 20 && .LCH WATCHES/WARNINGS/ADVISORIES... LA...Heat Advisory from noon to 7 PM CDT Monday for LAZ028-029. TX...None. GM...None. && $$ SHORT TERM...15 LONG TERM....15 AVIATION...05
Area Forecast Discussion
National Weather Service Elko NV
1248 PM PDT Sun Jul 28 2024 .SYNOPSIS...Sunny conditions with haze at times due to smoke from CA wildfires for today and Monday. Visibility may be lower in Humboldt county being in closer proximity to the fires. Comfortable afternoon highs in the upper 80`s and lower 90`s on Sunday will see a slight increase Monday afternoon. Precipitation and thunderstorm chances are absent from the region through Thursday night. && .SHORT TERM...Some visibility issues associated with smoke from nearby CA wildfires will be the main issue in a fairly quiet short term forecast period. Upper level SW flow presides over the state between the burgeoning ridge to the southeast and an upper level trough straddling the Pac NW coast keeps available moisture and therefore chances for convection away from the CWA in the early week period. Wildfire smoke will transition mainly across the northern counties of Nevada Sunday and Monday though Nye and White Pine county will see some temporary low visibility conditions from ongoing southern California fires as well. Poor air quality Sunday and Monday could lead to health related issues for sensitive groups and precautions should be taken to limit exposure. Daytime high`s in the 80s and low 90s across the CWA today will increase slightly into the work week as the aforementioned ridge continues to build into region Monday and Tuesday AM. .LONG TERM...Tuesday through next Sunday. All models show a weak upper trough moving across the northern Rockies with a large upper ridge spanning across the southern United States. Moisture and instability will be limited across the north and could lead to an isolated dry thunderstorm during the late afternoon hours. Otherwise, haze and smoke will be prevalent due to wildfires burning across the western United States. Highs will be in the 80s and 90s. Winds will be out of the west and southwest with gusts to 25 mph. Look for quiet weather during the overnight though skies could be haze and smoke filled. Overnight lows will be in the 40s and 50s. For Wednesday through Saturday, the large upper level ridge will gradually move westward and intensify. This means afternoon high temperatures will climb back to above normal levels. On Wednesday highs are expected to remain in the 80s and 90s, with warming conditions into the 90s and low 100s Thursday and Friday. It is still too far to look at the possibility for heat products though something may be needed and will keep a watchful eye. Overnight lows will be in the 50s and 60s. Winds will generally remain light each afternoon. Model simulations are showing the upper ridge circulation setting up near the four-corners area on Friday and Saturday. This will result in a southerly flow that will guide moisture northward. Because of the rather dry pattern beforehand, thinking is that most, if not all, storms will be dry on Friday but a mix of wet and dry storms on Saturday. Will need to keep an eye on this event as well due to possible fire weather concerns and dry thunderstorm coverage. By Sunday, models show the position of the ridge around the states of Utah and Arizona. This will keep the moist southerly flow going and believe another round of wet and dry thunderstorms will develop during the late morning and early afternoon hours. Highs will be in the 90s to low 100s while overnight lows will be in the 50s and 60s. && .AVIATION...VFR conditions will continue for the next 24 hours for the forecast area, though temporary MVFR/IFR conditions are possible due to smoke from California wildfires for the KWMC, KBAM, KEKO, and KELY terminals. Otherwise, weather conditions persist across northern and central Nevada. Winds will diminish this evening but will pick back up Monday W-SW10-15G25KT. && .FIRE WEATHER...Mostly sunny today and Monday with west to southwest winds of 10 to 20 mph gusting 25 to 30 mph in the afternoon and early evening hours. HRRR model guidance drifts near surface smoke over the majority of the CWA today and Monday before 20z when better ventilating SW flow will push some of the smoke to the northeast away from the region. However, the model has a new plume of smoke making its way into Humboldt county early Tuesday morning. Some concerns over fire risk in elevated portions of White Pine county on Monday afternoon exist due to low RH/wind but model guidance has winds borderline at best, so criteria is not present for issuing any products. Partners, however, should monitor elevated region in the area. Precipitation and thunder chances are absent from the area through Thursday night. Models currently have isolated dry thunderstorms across central and northeastern zones Friday afternoon, however the air is so dry that the expected weak instability may only result in afternoon cumulus cloud build- ups.However, better chances for isolated dry thunder in eastern portions of the region exist Saturday afternoon with slightly more monsoonal moisture available in those regions. && .LKN Watches/Warnings/Advisories... None. && $$ 99/86/86/99
Area Forecast Discussion
National Weather Service Pocatello ID
250 PM MDT Sun Jul 28 2024 .SHORT TERM...Tonight through Monday Night. Early afternoon satellite imagery shows a departing H5 trough over Montana as drier, zonal flow builds in overhead Even with this drier airmass building in from the west, we will see some isolated shower and thunderstorm activity primarily along the Montana and Wyoming border regions associated with lingering moisture behind yesterdays exiting system. This is where the HREF model probability of thunder shows a 10-30% chance with less than a 10% chance elsewhere. Highs today will remain seasonably cool in the 70s and 80s with wind gusts peaking during the afternoon hours around 15-30 mph. For Monday, attention turns to our next H5 trough as it begins to move onshore to the PacNW while we transition from zonal flow to carrying a SW component. This will bring highs up into the 80s/90s across our lower elevations as synoptic winds see an increase associated with 20-35 kt 700 mb winds shifting overhead. This will support breezy winds during the afternoon hours with wind gusts to around 20-40 mph which with a combination of low minimum humidities in the teens and 20s, will support near critical to critical fire weather conditions. Ahead of the arrival of this trough for Tuesday, conditions will remain dry on Monday into Monday night with isolated showers and storms building into the CNTRL Mountains early Tuesday morning. MacKay .LONG TERM...Tuesday through next Sunday. The long-term portion of our forecast will feature a bi-modal solution. First, an organized shortwave trough is well-advertised by all models to cross the region Tue, bringing isolated to scattered showers and t-storms and breezy conditions all during the afternoon and early evening. An early glance at NAMNest and GFS forecast soundings don`t offer much in the way of support for any organized severe wx...lapse rates are steep and the low-levels lean dry which might support some pulse-mode gusty winds, but CAPE profiles are tall/skinny with DCAPE less than 1,000 J/kg and zonal westerly flow throughout the column (thus very little shear). The strongest cores may favor the Central Mountains, due largely to potentially higher CAPE/instability up in our northern CWA. We`ll continue digging into all of this in the days ahead. For now, NBM PoPs seemed a bit low and largely limited to the nrn Central Mntns and MT border, so increased PoPs and started to "brush" them further south into the nrn Snake Plain and terrain areas across the horizontal central 1/3rd of our CWA, a bit closer to the ECMWF/Canadian solution for where precip may develop. Hopefully we`ll see this trend natively in NBM guidance as well in the days ahead. Still, don`t expect a washout anywhere. Expect high temps Tue to run 5-7 degrees cooler than Mon generally topping out in the low 80s outside of a few cooler mntn valleys...this will be 5-10 degrees below climatological normals for late July and may be another factor that could keep convection in check Tue afternoon as convective temps still need to be breached to support t-storm development. Second (and this isn`t good news if you`ve recently been struggling with heat and air conditioning issues like this forecaster)...a large, stagnant dome of high pressure is forecast by all long-range deterministic models to become re-established over the Four Corners region for the rest of the week into next weekend (maybe beyond?), perhaps shifting westward just slightly with time. This is well- supported by all 500mb height clusters as well with only slight differences in exact amplitude and axis position...daily EOF patterns in the ensemble space also reflect these relatively minor differences with no dominant/consistent source of uncertainty and no signs of any other dominant wx system breaking into/breaking down the dome. We`ll certainly watch to see if any shortwave trough/disturbance riding over the ridge can flatten it enough to impact SE Idaho...either with wind or a bump in t-storm potential via broad lift, but otherwise this whole synoptic pattern spells two things: MORE HEAT, and perhaps an eventual increase in monsoon moisture working up the back/west side of the ridge. At this time, NBM guidance supports a warming trend Wed/Thu with temps stabilizing and maxing out in the upper 90s to low 100s by Fri/Sat/Sun in our normally warmest locales (ern Magic Valley, Raft River region, Snake Plain, and Challis). With potentially modest overnight temp recovery, a HEAT ADVISORY is not completely out of the question for some portion of this general period, and the ECMWF Extreme Forecast Index (EFI) paints widespread 0.7 to 0.9 values by Sat and Sun, suggesting that even compared to this normally hot time of year, the overwhelming majority of EC ensemble members are coming in warmer than the model climatology and thus confidence is increasing in a heat wave returning to the region. Long-range models (especially the higher-resolution Canadian) also show hints of that increasing monsoon moisture making it up into Idaho as early as Fri, but especially Sat/Sun. This isn`t yet really reflected in NBM PoPs, but at least some potential for isolated showers/t-storms should eventually manifest diurnally each afternoon starting sometime during this window. At this time, GFS PWATs increase the most starting Sun but still hold below 1.00", so hard to tell yet whether or not heavy rainfall will become a concern. Don`t forget about your heat safety precautions! Overall, didn`t deviate significantly from NBM guidance and WPC QPF from Wed onward. - KSmith && .AVIATION...For the 18Z TAFS through 18Z Monday. Still expecting a diurnal increase in FEW to SCT clouds this afternoon with some potential for a few isolated t-storms as a shortwave trough brushes across the region from the north. HREF CAMs all continue to lean much drier compared to the past several days, but more than one member develops convection near both KSUN and KDIJ, so added VCTS to KSUN and adjusted start/end times at both terminals (18-01z/noon-7pm KSUN and 20-02z/2-8pm KDIJ). Overall potential is higher at KDIJ compared to KSUN, and we`ll be keeping a close eye on KIDA as well in case convection tries to get close to the airport from the north (very low confidence). Otherwise, expecting a relatively low-impact day as far as traditional TAF elements are concerned with fairly modest winds (BUT we`ll talk about wildfire smoke in a moment). Overall confidence in the wind and cig forecast is high with excellent agreement among our various models and guidance sources, unless a t-storm outflow boundary is able to escape into the ern Magic Valley/Snake Plain corridor and modify wind gusts/direction for a few hours at KBYI/KIDA/KPIH...this will be monitored in real-time and captured in an amendment if possible/if needed. Lower PWATs generally below 0.7", DCAPE over 1,000 J/kg and dry low-levels advertised in NAMNest/RAP forecast soundings, and a few simulated gusty outflows on various HRRR runs all suggest outflow boundary development/propagation is certainly within the realm of possibility. The one other likely impact to aviation will be continued wildfire smoke generally advecting in from the west. Satellite trends suggest some degree of smoke/haze is already blanketing most of the state of Idaho from the Snake Plain north/west (banking up against the terrain south/east of KPIH/KIDA), although so far this has only manifested in reduced vsbys in the Treasure and Magic Valley areas (KBYI included...currently running at 6SM). Forecasting smoke is difficult and overall confidence in exact numbers is somewhat low...but the general trend on both the HRRR and RAP smoke models is for smoke to slightly increase over the course of this afternoon and tonight, and vsbys as low as 3-5SM have been observed upstream at KMUO and KTWF. Have tried to capture these general trends in the 18z TAF package with decreasing vsbys to 5-6 SM over time at KIDA and KPIH, and potentially as low as 4 SM at KBYI by tonight (based on upstream obs), while KDIJ may stay more protected by surrounding terrain. Have held at 6SM for now at KSUN given their nocturnal wind shifts into the NW which may interrupt transport of the smokier air up- valley from the ern Magic Valley. All things considered, the smoke may end up being the #1 aviation concern over the next 24-36 hours for most aircraft. Looking ahead to Mon, expect a dry day with a slight increase in diurnal afternoon winds out of the WSW, especially for KSUN and the Snake Plain terminals where gusts of 18- 30kts will likely be needed. - KSmith && .FIRE WEATHER... The primary impact today will be isolated showers and thunderstorms along the Montana and Wyoming border regions where the HREF model probability of thunder shows a 10-30% chance with less than a 10% chance everywhere else. Have held off on any RFW issuance at this time given coverage on the latest CAMS has remained more isolated. Winds gusts today will range from 20-30 mph with afternoon humidity dropping to the teens and 20s. For Monday, an approaching Pacific trough will move onshore to the PacNW and help to introduce an increase in winds in addition to slightly warmer temperatures given increasing SW flow. This flow regime will support more widespread RHs in the teens with the coverage of a combination of wind gusts to 25-35 mph and minimum RHs in the teens supporting a RED FLAG WARNING in effect from 1200 to 2100 for FWZ 410, 475, and 476. Elsewhere, winds and RH will be more marginal but certainly support near critical fire weather conditions. Conditions will remain dry on Monday outside of a 5-15% chance of showers and storms along the Montana border region. On Tuesday, that aforementioned Pacific trough will pass overhead and will lead to isolated to scattered showers and thunderstorms in addition to maintaining elevated wind gusts peaking around 20-40 mph in the afternoon. The more noticeable difference on Tuesday will be the increase in humidity bottoming out in that 20-40% range during the afternoon hours. Showers and thunderstorms will depart east Tuesday night as drier conditions build in from the west as high confidence supports a H5 ridge of high pressure building in overhead for the remainder of the week. This will support a return to very dry conditions starting Wednesday as temperatures see a gradual warming trend through the weekend. We may see isolated showers and storms building in late next week as weak monsoon moisture rotates clockwise into SE Idaho but confidence is low this far out. MacKay && .AIR QUALITY... Air quality and visibility continue to be impacted from wildfire smoke associated with several large wildfires currently burning in California, Oregon, and Nevada. The latest HRRR smoke model shows increasing smoke building into SE today into Monday with increased uncertainty on exactly how much of that smoke will remain in place on Tuesday as an Pacific trough passes overhead. Expect continued degraded air quality into Monday with less confidence into Tuesday. Air Quality Alerts remain in effect for much of eastern Idaho, relayed from our partners at the Idaho Department of Environmental Quality (ID DEQ). The current AQI as of 2 PM MDT Sunday ranges from moderate across to very unhealthy across all of SRN Idaho with satellite imagery showing widespread smoke situated overhead. MacKay && .PIH WATCHES/WARNINGS/ADVISORIES... Red Flag Warning from noon to 9 PM MDT Monday for IDZ410-475-476. && $$
Area Forecast Discussion
National Weather Service Topeka KS
542 PM CDT Sun Jul 28 2024 .KEY MESSAGES... -Scattered showers and isolated storms linger this afternoon, with slight chances continuing overnight. -Upgraded the Excessive Heat Watch to a Heat Advisory and Excessive Heat Warning for the upcoming workweek. -A front will move into the area Thursday, which will provide some, although not much, temperature relief. && .DISCUSSION... Issued at 311 PM CDT Sun Jul 28 2024 This afternoon, scattered showers and isolated storms have continued to develop across the area, appearing to be the result of continued isentropic ascent. Thinking that this activity will diminish with time into the late afternoon hours. This evening and tonight, a weak H5 shortwave trough and associated PVA will move over Nebraska and northern Kansas within the westerly mid level flow. Confidence is not high on whether storms will develop and make it into northern and northeastern sections of KS, so have trimmed back POPs a little bit more. CAMs have not been consistent with each other or run-to-run, lending more to the decreasing confidence levels. The last few runs of the HRRR have also shown some development in northeast KS later Monday morning, but with a fairly dry profile, large amounts of MLCIN and no upper level support, have kept POPs less than 15 percent. Attention will then turn to the building heat with upper level ridging and associated thicknesses increase over the area. Due to growing confidence, have gone ahead and upgraded the Excessive Heat Watch that was issued yesterday to a Heat Advisory in far northern Kansas from Monday afternoon through Wednesday, and to an Excessive Heat Warning for the rest of the area from Monday afternoon through Thursday. Actual temperatures are forecast to reach triple digits much of this time. That combined with dew points in the upper 60s and low 70s will create heat index values between 105 and 112 degrees each afternoon. Boundary layer mixing and occasional cloud cover could still cause adjustments to the temp/heat index forecast, but it should be hot enough to satisfy advisory and warning criteria. Midweek, a mid-level trough will move through the Midwest, bringing a cold front into northern KS Wednesday night/early Thursday and pushing the center of the mid-level ridge westward. POPs increase near the boundary early Thursday, which is our next best chance for some precipitation beyond tonight. While Thursday still appears very warm, especially south of Interstate 70 where the warning will remain in effect, the front should provide at least some, although not much, relief for late in the week. && .AVIATION /00Z TAFS THROUGH 00Z TUESDAY/... Issued at 542 PM CDT Sun Jul 28 2024 Models prog the nose of the low level jet setting up over northwestern MO. So think the bulk of any elevated storms should remain northeast of the terminals. There is some indication of isentropic upglide between 700 and 600MB across central KS overnight and may be what some of the CAMs are picking up on. With probs around 20 percent, will keep a dry forecast for now and watch of indications of the lift developing. VFR conditions are expected to prevail otherwise. Will maintain some LLWS in the forecast for a 40KT to 50KT jet and some decoupling of the boundary layer overnight. && .TOP WATCHES/WARNINGS/ADVISORIES... Heat Advisory from 1 PM Monday to 7 PM CDT Wednesday for KSZ008-KSZ009-KSZ010-KSZ011-KSZ012. Excessive Heat Warning from 1 PM Monday to 7 PM CDT Thursday for KSZ020-KSZ021-KSZ022-KSZ023-KSZ024-KSZ026-KSZ034-KSZ035- KSZ036-KSZ037-KSZ038-KSZ039-KSZ040-KSZ054-KSZ055-KSZ056-KSZ058- KSZ059. && $$ DISCUSSION...Teefey AVIATION...Wolters
Area Forecast Discussion
National Weather Service Las Vegas NV
715 PM PDT Sun Jul 28 2024 .SYNOPSIS...Dry and breezy conditions with seasonable temperatures can be expected through Tuesday. Thereafter monsoon moisture creeps back into Arizona, returning precipitation chances to Mohave County midweek. Elsewhere, expect persistent dry conditions and increasing temperatures heading into the weekend. && .UPDATE...Will update the smoke/haze grids with the latest incoming HRRR Smoke guidance. Tonight`s smoke plume from the Borel Fire on a nearly identical trajectory as last evening. However, magnitude in the amount of smoke looks to be less. Satellite shows the plume cutting across Death Valley NP, southern Nye County with leading edge around Indian Springs. HRRR smoke guidance indicates the worst part of the smoke plume will stay to the north and west of Las Vegas with a slightly more southerly trajectory keeping Inyo, Nye and Esmeralda Counties under the worst air quality. Currently, AQI sensors at Lone Pine and Keeler CA in the Owens Valley are in the unhealthy and unhealthy for Sensitive Groups category. Otherwise, it will stay breezy at times with near normal temperatures into Tuesday. && .PREV DISCUSSION...1208 PM PDT Sun Jul 28 2024 .DISCUSSION...through next weekend. Aside from lingering smoke, skies are mostly clear this afternoon with a broad southwesterly flow aloft keeping conditions dry and stable. Smoke density overall has trended downward from yesterday, but we continue to see a layer of smoke induced haze cloud our skies, particularly across our northern and western zones. This afternoons visible satellite imagery depicts smoke plumes in Kern County once again becoming agitated with increasing surface winds and a deepening mixed layer which will continue to develop through the daylight hours. This promises additional smoke will sweep eastward across Inyo, Nye, and Lincoln Counties. A tendency for increasingly southerly wind components will also help this smoke drift further west this evening and overnight, impacting the Owens Valley and Esmeralda County. Alternatively, significantly less smoke is expected to impact the Las Vegas Valley through Monday, staying mostly confined to points north and west. Aside from the smoke, Western US troughing is keeping our region dry and relatively cool compared to the past several weeks. Temperatures in Las Vegas are running several degrees cooler than this time yesterday, and we stand at least a small chance to break our record ongoing consecutive 105F+ streak. Las Vegas has so far observed 38 consecutive days of temperatures equal to or above 105 degrees as of yesterday. The previous record was 25 days in 2017. The general weather pattern will change little through Tuesday, with continued afternoon breezes and fairly seasonable temperatures expected. By midweek onward, high pressure will begin to rebuild over the Four Corners, setting the stage for a more typical mid- summer weather pattern and a slow return of monsoonal moisture to Arizona. Thunderstorm chances creep back into Mohave County Wednesday onward, while other areas remain dry with a slow warming trend. There are hints at a weak inverted trough feature lifting around the high out of southern Arizona and into the Western Mojave Desert on Thu/Fri, which sometimes can prove to be a favorable thunderstorm pattern. However, guidance is varied on both its strength and moisture availability, and NBM pops remain pretty sparse outside of Mohave county until the weekend. By Saturday and Sunday, precipitation chances begin to spread west into the eastern Mojave Desert, while temperatures climb and many of the lower deserts rise into the major heat risk category. && .AVIATION...For Harry Reid...Breezy southwest winds with occasional gusts to 25kts will continue into this evening. Winds will diminish overnight tonight, with speeds likely falling below 10kts by midnight. Breezy southwest winds will return Monday, although afternoon gusts should be lower than today, topping out around 20kts. Smoke from wildfires burning in Kern County, CA, will continue to move across the area today. The smoke is expected to remain elevated, and no significant reduction in surface visibilities is expected. However, slantwise visibilities will likely be reduced, especially in the Beatty and Mormon Mesa corridors. The latest HRRR smoke guidance shows the plume shifting further north overnight and Monday, reducing impacts to the Las Vegas Valley. Otherwise, no operationally significant cloud cover is expected through Monday. For the rest of southern Nevada, northwest Arizona and southeast California... Breezy south to southwest winds with gusts to 25kts will continue at most regional TAF sites today. All areas should see winds fall to 12kts or less overnight before increasing to levels similar to today on Monday. Smoke from wildfires burning in Kern County, CA, will continue to affect portions of the region today. Web cameras from across the region show the smoke plume is staying elevated near regional TAF sites, and the smoke is expected to remain elevated across most areas into Monday. However, slantwise visibilities will be reduced, with the largest reductions expected across northern San Bernardino, central and southern Inyo counties, and southern Nevada north of the Las Vegas Valley. Otherwise, no operationally significant cloud cover is expected through Monday. && .SPOTTER INFORMATION STATEMENT...Spotters are encouraged to report any significant weather or impacts according to standard operating procedures. && $$ UPDATE...Pierce DISCUSSION...Outler AVIATION...Planz For more forecast information...see us on our webpage: https://weather.gov/lasvegas or follow us on Facebook and Twitter