Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 10/04/22

Area Forecast Discussion...Updated
National Weather Service Billings MT
833 PM MDT Mon Oct 3 2022 .UPDATE... Decreased PoPs a little this evening as the radar is not showing much for returns in the southeast. Also, expanded the fog potential a little more as soundings are pretty saturated in the southeast overnight from recent RAP runs. It still looks like the main fog potential will be east of Billings. Reimer && .DISCUSSION... Tonight through Tuesday night... An upper low centered over east-central Montana will move southeastward into South Dakota this evening into Tuesday. As it does so the overall trend will be for showers and thunderstorms to diminish from northwest to southeast. For this afternoon into this evening, showers and a few embedded thunderstorms are likely mainly over southeast MT as a disturbance rotates around the upper low. Over south central MT-north central WY, isolated showers are possible through late this afternoon due to some weak instability and moisture in place. As the evening goes on the chance of showers will decrease as the disturbance moves out of the area and instability decreases with the loss of solar heating. Additional rainfall for southeast MT will be around 0.10 inches. Over south central MT and north central WY, upper ridging will then slide eastward into the area and produce drier conditions tonight. As skies clear out tonight, patchy fog is possible. Confidence of fog is higher from Rosebud County eastward. Any fog should burn off by 10 AM MDT Tuesday. Upper ridging will dominate the weather for much of the area Tuesday with dry and warmer conditions. There is a slight chance of a shower over southern Carter County Tuesday as another disturbance moves southeastward over the area on the western side of the upper low. By Tuesday night, the upper low will have moved far enough away from the region that the entire area will be dry. High temperatures will be in the 60s and 70s Tuesday. Low temperatures will generally be in the 30s and 40s tonight and 40s Tuesday night. RMS Wednesday through Sunday... Warm dry pre-frontal day on Wednesday with sunny skies and temperatures in the 70s. Cold front moves into Wednesday night from the northeast bringing low chances for precipitation but much cooler temperatures for Thursday with highs mainly in the 50s to around 60 degrees. Temperatures climb back to seasonal levels with dry northwest flow over the area through the weekend. Some ensemble members bring a pretty good cold front through late Saturday into Sunday, but latest NBM temp guidance and spread have not caught onto this feature yet, so may see cooler temperatures and some precipitation chances for the end of the weekend that are not currently in the forecast. Chambers && .AVIATION... Areas of fog are expected to develop late evening into the overnight hours with potential for fog at all TAF sites, but with highest confidence in SE Montana for KMLS and KBHK. Where fog develops expect IFR to LIFR conditions to persist through about 15z Tuesday morning before beginning to lift/break up. Chambers/Vertz && .PRELIMINARY POINT TEMP/POPS... Tue Wed Thu Fri Sat Sun Mon ----------------------------------------------------------- BIL 046/070 046/074 046/060 041/064 042/068 044/067 044/072 00/U 00/U 11/B 00/U 00/B 10/U 01/U LVM 040/072 040/075 040/065 038/068 038/070 038/069 038/072 00/U 00/U 00/B 00/B 00/B 00/B 01/U HDN 043/071 040/076 042/063 037/065 037/069 039/070 039/073 10/U 00/U 11/B 00/U 00/B 10/U 00/U MLS 047/068 045/074 044/055 035/061 038/066 040/067 040/070 20/U 00/U 12/W 00/U 00/U 00/U 00/U 4BQ 046/066 043/073 044/057 036/061 039/066 040/067 041/071 21/B 00/U 12/W 10/U 00/B 00/U 00/U BHK 047/066 044/072 037/051 029/057 034/063 037/064 038/068 21/B 00/U 12/W 00/U 00/U 00/U 00/U SHR 042/068 041/073 041/063 038/064 038/068 039/068 038/072 20/U 00/U 02/W 10/U 00/B 11/U 10/U && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...None. WY...None. && $$
Area Forecast Discussion
National Weather Service Cheyenne WY
534 PM MDT Mon Oct 3 2022 .SHORT TERM...(This evening through Wednesday night) Issued at 227PM MDT Mon Oct 3 2022 The area continues to be impacted by a persistent, slow-moving ULL to our north across eastern Montana this afternoon. Further upstream, an amplifying upper level ridge will become entrenched across the Pacific Northwest this afternoon, allowing the ULL to begin to slide to the south and east. At the surface, RAP frontal analysis depicts a stationary front draped across Southern WY, primarily along the I-80 corridor. This stationary frontal boundary extends into southwest NE before it transitions northward into the northern Plains of the Dakotas. Weak instability is present this afternoon as breaks in the cloud cover, lapse rates from the surface to the mid-levels of 6.5-8 degrees C/km, and abundant moisture have contributed to shower and thundershower activity development by 18Z today. Brief, gusty and erratic winds up to 35mph have been observed with some of the rain shower activity. Model soundings do show inverted-V features from about 700mb down to the surface, so rain shower activity with embedded thunderstorms are likely to result in continued gusty winds through the evening hours. The NamNest and HRRR output for this afternoon shows scattered showers and thunderstorms occurring in SE WY through approximately 6Z, but the northern forecast zones of SE WY and the NE Panhandle do have the opportunity to see scattered showers and thunderstorms through the overnight hours to near daybreak of Tuesday. This is supported by upper level dynamics showing multiple shortwaves associated with the upper level trough axis pushing through the region today into tomorrow morning. Due to decreasing cloud cover in our western forecast zones as the ULL slowly moves to the east and south, temperatures will decrease to near or below freezing for several areas west of the Laramie Range. Areas of frost are looking highly favorable for the valley regions of Carbon and Albany County due to the cold pooling of the dense, cool air. Have decided against a frost/freeze headline for the overnight period into Tuesday morning due to only areas of frost being forecast. This may need another evaluation after the evening model guidance arrives to determine whether a short-term headline issuance is necessary. The remainder of Tuesday will see isolated showers and a possible thunderstorm east of the I-25 corridor through the late afternoon hours due to the ULL moving east, and away from the region. Mostly clear skies on Tuesday night will bring morning lows in the upper 20s to low 30s for several areas west of the Laramie Range. The Snowy/Sierra Madre mountain ranges are likely to see middle to upper 20s. It will be another opportunity for possible frost/hard freeze headlines. Mostly sunny skies will be present on Wednesday as pleasant conditions return to the cwa. Afternoon highs will reach the 60s and 70s for a majority of the area. However, the higher terrain of the Snowy/Sierra Madre Ranges will struggle to reach 50 degrees. Mostly clear skies on Wednesday night will allow for most areas to creep a couple degrees colder by sunrise Thursday. Morning lows will range from the upper 20s west of the Laramie Range, to the upper 30s east of the Laramie Range. This will be the first opportunity of the month for frost being possible along the Pine Ridge corridor of Converse, Niobrara, Sioux, and Dawes County. Another potential area will be along HWY 26 in Goshen County toward the Scotts Bluff County corridor. Will need to keep an eye on this for possible cold temperature headlines into the NE Panhandle. Overall, expect a pleasant next couple of days with the return of sunshine to region. .LONG TERM...(Thursday through Monday) Issued at 227 PM MDT Mon Oct 3 2022 A cool & fairly quiet extended forecast period can be expected for southeast Wyo & the western Neb Panhandle beneath fairly dry north westerly flow aloft. A series of weak disturbances embedded within the larger scale flow pattern will contribute to occasional shower chances through the period, but any precipitation should be fairly light. A cold frontal passage Thu night & Fri should be the signal for more widespread frost as lows fall into the lower 30s for much of the area. && .AVIATION...(For the 00Z TAFS through 00Z Tuesday evening) Issued at 533 PM MDT Mon Oct 3 2022 Scattered shower and thunderstorm activity will continue through the evening hours. Gusty, erratic winds as well as small hail is possible in storms. Conditions will likely remain VFR for most terminals. Brief MVFR to IFR conditions are possible due to visibility drops in moderate to heavy rain. Light scattered showers may continue into the overnight hours. Tuesday looks mostly dry with VFR conditions expected. && .FIRE WEATHER... Issued at 227 PM MDT Mon Oct 3 2022 Fire weather concerns will remain at none to low due to recent precipitation and cool temperatures across the area. Peak wind gusts are not expected to be higher than 20 mph today unless there is a nearby thunderstorm, where max wind gusts to 35mph will be present. Minimum RH values will be hover near 40% today and tomorrow, before decreasing to 30% by the middle of the week. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...None. NE...None. && $$ SHORT TERM...BW LONG TERM...CLH AVIATION...SF FIRE WEATHER...BW
Area Forecast Discussion
National Weather Service Green Bay WI
1035 PM CDT Mon Oct 3 2022 Updated aviation portion for 06Z TAF issuance .SHORT TERM...Tonight and Tuesday Issued at 225 PM CDT Mon Oct 3 2022 The latest RAP analysis and satellite/radar imagery show high pressure centered over the central Great Lakes and low pressure positioned over the northern Plains. Like the past several days, mid-level clouds continue to pour over the ridge and into the western half of Wisconsin. A few sprinkles reached as far east the US-51/I-39 corridor this morning, but have since dissipated. As large scale features slowly move east over the next 24 hours, rain chances and fog potential are the main forecast concerns. Tonight...The mid-level ridge axis will slowly move east into northern Lake Michigan. This should allow clouds above 10 kft to push further east across northeast WI. However, dry air below this level will continue to circulate around the high and across northeast WI, which will thwart precip chances over the eastern part of the state. With shortwave energy approaching western Lake Superior late tonight, it`s possible a few sprinkles could make a run at north-central WI after midnight. Temps should be warmer tonight with more in the way of cloud cover. Some lows may still approach the low 40s over east-central WI where clearing will hold on the longest. The warmer temps should also mitigate the fog threat. Tuesday...The weak impulse will lift northeast over far western Lake Superior, while low pressure over the Dakotas will move slightly closer to the region. Mid and high clouds will continue to be more widespread over central and north-central WI, but think the chance of sprinkles will depart early Tuesday morning with the weak impulse. Southwest winds will draw in warmer air with highs in the low to mid 70s away from Lake Michigan. .LONG TERM...Tuesday Night Through Monday Issued at 225 PM CDT Mon Oct 3 2022 Forecast concerns will be centered on the Wednesday night to Thursday night period, when a strong cold front brings showers, lake-effect snow in north central WI, gusty northwest winds, possible gale force gusts on Lake Michigan, and much colder temperatures. The forecast area will remain on the northwest periphery of a large high pressure system Tuesday night. A weak upper level trough will approach the forecast area Wednesday afternoon, and may produce a few light showers in north central and central WI late in the day. Mild conditions will continue, with lows in the 45 to 50 range Tuesday night, and highs in the upper 60s and lower 70s Wednesday. A powerful cold front will approach the area Wednesday evening, then move through the forecast area overnight into early Thursday. Showers will increase, especially across the northeast half of the forecast area, as strong frontogenetic forcing moves through. Strong CAA will occur in the wake of the front, with 850 mb temperatures in east central WI dropping from around 10 C to -4 C on Thursday. Persistent cold NNW-N flow and lake-850 mb delta-t`s of at least 20 C will lead to lake-effect in NC WI and Door County from Thursday afternoon through Friday morning. The first snow of the season is expected in north central WI Thursday night, though only light accumulations are anticipated in Vilas county. Winds will likely gust to 30 to 35 mph at inland locations Thursday afternoon and evening, with gusts to 35+ knots (gale force) on Lake Michigan. Temperatures will drop well below normal, with highs only in the 40s to around 50 by Friday. Continued the trend of increasing the blended model winds/gusts regionwide, and pops in NC WI (lake-effect), during the Thursday through Friday morning period. Dry conditions are expected for the weekend and early next week, with a gradual moderating trend. There could be some frost in the Fox Valley/lakeshore areas (where frost/freeze headlines are still being issued) on Friday night, but winds may be too strong for a widespread frost or freeze. && .AVIATION...for 06Z TAF Issuance Issued at 1035 PM CDT Mon Oct 3 2022 VFR conditions are expected through the TAF period. Low pressure slowly moving across the northern Plains and northern Mississippi Valley will continue to spread a mix of mid and high clouds across the area. A few showers and sprinkles will be possible at times at RHI/AUW/CWA but will have no aviation impact. Winds will remain light, mainly out of the south/southwest. && .GRB WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM.....MPC LONG TERM......Kieckbusch AVIATION.......Bersch
Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
958 PM EDT Mon Oct 3 2022 .SYNOPSIS... An upper low will slowly drift east across the Mid-Atlantic States to the Atlantic Ocean through Tuesday, maintaining a northerly breeze and scattered clouds. Temperatures will slowly warm through late in the week, before a dry cold front ushers in colder temperatures for this weekend. && .NEAR TERM /THROUGH TUESDAY/... Evening Update...No sigfnt changes needed over the near term. Upper clouds continue to traverse the area associated with a passing vort wave. Expect another h5 wave overnight keeping some measure of upper moisture across the FA, yet not enuf to offset good rad cooling conds over most locales. The mtn valleys will be favored for any dense fog that that forms as the latest RAP sfc CPDs become saturated before daybreak. Otherwise, expect efficient cooling and mins below normal by a few degrees outside of NE GA and the wrn Upstate where cloudiness may linger longer. Otherwise...An upper-low will meander just south of the Mid- Atlantic region with the low pressure center remaining NE of the western Carolinas and NE GA through the near term fcst period. This will allow northerly cyclonic flow to continue over the Carolinas and NE Georgia leading to below climo temps through Tuesday. The southern periphery of a sfc ridge will continue to extend into the CWA into Tuesday. This will allow dry conditions to continue. Taller ridgetops have the potential to see some patchy frost with lows expected to fall into the mid to upper 30s. Wind direction turns NW`ly on Tuesday, with wind speeds becoming low-end breezy again. Highs will be a tad warmer Tuesday compared to today, but still remaining around 2-5 degrees below climo. && .SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/... As of 155 PM EDT Monday: Heights ridge Wednesday as short wave ridge builds in behind the departing remnants of Ian with nearly zonal flow for Thursday. Warm and dry high pressure builds in at the surface. Highs a few degrees below normal Wednesday rise to a little above normal for Thursday. Lows around 10 degrees below normal Tuesday night rise a few degrees for Wednesday night. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... As of 135 PM EDT Monday: Broad upper trough remains over the eastern CONUS through Sunday with heights rising slightly on Monday as a ridge begins building over the MS valley. At the surface, a dry cold front crosses the area Friday ushering in a cold air mass across the area. High pressure builds in through the period with the air mass slowly moderating. Highs Friday will be near to a few degrees above normal then falling to around 10 degrees below normal through the rest of the period. Lows start out around 5 degrees below normal then drop to around 15 degrees below normal for Saturday night and Sunday night. These temperatures will bring a threat of a widespread freeze to a significant portion of the NC mountains with widespread frost potential for the rest of the mountains and NC foothills and NW Piedmont, along with normally colder and more sheltered locations across the rest of the area. As usual, stay tuned to the latest forecasts. && .AVIATION /02Z TUESDAY THROUGH SATURDAY/... At KCLT and elsewhere: The pattern remains conducive for good rad cooling overnight, however, think the best chance of fog/StCu will be across the NC mtn valleys including KAVL where sfc tdd/s and cpd/s remain the lowest. The main threat at KAVL will be fog with VLIFR VSBY probable btw 10z-13z. An offshore sfc low will push in the midAtl region Tue and interact with hipres building in from the northwest. This will make for nw/ly sfc winds thru the latter periods aft a morning inversion becomes well mixed. Outlook: Surface high pressure will remain in place through Thursday before a dry cold front tracks across the area on Friday. High pressure builds back in behind the departing front this weekend. This will lead to dry and generally VFR conditions through the end of the week outside of mountain valley fog potential each morning. && .GSP WATCHES/WARNINGS/ADVISORIES... GA...None. NC...None. SC...None. && $$ SYNOPSIS...DEO NEAR TERM...AP/SBK SHORT TERM...RWH LONG TERM...RWH AVIATION...SBK
Area Forecast Discussion
National Weather Service Gray ME
1134 PM EDT Mon Oct 3 2022 .SYNOPSIS... High pressure builds in from the north through at least Midweek providing for fair weather, warm days, and cool crisp nights. The only fly in the ointment may be a storm system to our south that may graze the region with unsettled weather on Wednesday. A cold front looks to approach late Friday bringing a chance of showers. Much cooler temperatures are then expected over the weekend. && .NEAR TERM /UNTIL 6 AM TUESDAY MORNING/... 1130pm Update...Temperatures north of the lakes region in NH and Sebago Lake in ME have largely fallen into the 30s at this hour. A thicker band of cirrostratus has been pivoting northward and has stalled temp declines or even bumped temps up a couple degrees. This has again been refined to the southern half of the CWA, but will likely persist northward into regions already in the mid to upper 30s. 820pm Update...The densest cirrus shield over southern NH continues to erode over central NH and far southern ME. This is most apparent on WV imagery and 00z GYX RAOB. Don`t expect these to impact radiational cooling too much outside of southern NH where sky cover will be most dense. Area temperatures are within a couple degrees of last night`s temps at this hour...perhaps a little warmer across the mountains/foothills and cooler along the immediate coast. Frost/Freeze headlines are in good standing, but it will be a close call for coastal Cumberland/York. With light winds from the NNW draining across the interior butting up against NE winds over the coastal waters, there will be a fairly tight temperature gradient just a couple miles inland, likely most apparent in valleys. Continued frost wording in sheltered locations for all but some of the immediate coastal communities, which admittedly takes up a large portion of these zones. Previous Discussion... The center of the surface high pressure will be centered over northern New England tonight, and very dry air and light to calm winds will provide excellent conditions for radiational cooling. Temperatures will drop very quickly toward and after sunset, and another night of frost and freeze conditions are expected, primarily away from the coast. The one stipulation is that quite a bit of cirrus may also stick around. There is more confidence in this being a factor across southern NH, potentially keeping the overnight temps a tad warmer and frost coverage low enough to leave Cheshire, Hillsborough, and Rockingham out of the Frost Advisory. Elsewhere, inland low temperatures ranging from the upper 20s to mid 30s have prompted Frost Advisories and Freeze Warnings to be issued for virtually the same areas as last night and this morning. && .SHORT TERM /6 AM TUESDAY MORNING THROUGH TUESDAY NIGHT/... High pressure remains in control on Tuesday, giving NH and western ME another dry day. High temperatures are generally expected to be similar or a degree or two warmer than today, but southerly upper- level winds ahead of an upper-level low over the Mid- Atlantic states will bring in a thickening cirrus layer into northern New England could keep temps a little lower than what is currently depicted in the forecast. Temperatures will start to moderate Tuesday night due to an increase in low-level moisture and also quite a bit of upper-level clouds sticking around. Mots will see overnight lows in the upper 30s to lower 40s, but more sheltered locations could still reach the mid 30s while also seeing some patchy frost. The low pressure of what`s left of Ian will slowly meander offshore of the Mid-Atlantic Tuesday night, and models are showing higher moisture along with some shower activity approaching southern NH and southwestern coastal ME. So will continue to mention the 20-30% PoPs across this area, which is supported by the 12Z HRRR and NAMNest. && .LONG TERM /WEDNESDAY THROUGH MONDAY/... An area of low pressure parked off the Mid Atlantic coastline will start to shift east northeast Wednesday. Short wave ridging slides over the area Thursday as a trough digs into the Great Lakes. The trough over the Great Lakes swings into New England Friday with a cold front crossing the region late afternoon and overnight. This front brings scattered showers over the interior with rain showers changing to snow showers in the higher terrain late Friday night and Saturday morning. Much cooler air arrives behind the front Saturday with upslope flow maintaining clouds and rain or snow showers in the mountains through Saturday night. High pressure then builds in from the SW late weekend into early next week for mostly dry weather and moderating temperatures. Cool and cloudy weather is expected across the southern third of the area Wednesday as steady ENE flow continues on the northern periphery of low pressure south of New England. Highs will range from the low to mid 60s across the south to the mid to upper 60s across the north where there will be more sunshine. The proximity of the low south of New England will also bring slight chances for showers across the NH/MA border into coastal Maine. Low pressure will make better progress to the ENE Wednesday night as the next upstream trough digs into the Great Lakes. Short wave ridging ahead of the next trough will slide overhead Thursday allowing for mostly sunny skies and highs rising into the upper 60s to low 70s areawide. As the next trough progresses eastward, low pressure will track through the St Lawrence Valley Friday. This low will drag a cold front across the area late Friday afternoon and overnight, although temperatures will likely warm into the 60s to low 70s ahead of the front. Chances for showers increase across northern and western zones Friday afternoon and overnight while areas near the coast may stay mostly dry. As colder air filters into the region rain showers may change to snow showers across the higher terrain late Friday night. Saturday will be much cooler as the cold front pushes well offshore with northern areas staying in the 40s and southern areas in 50s for high temperatures. Brisk west northwest will also be present over the area bringing wind chills well below freezing in the higher terrain. Upslope flow will also continue chances for rain and snow showers in the mountains for much of Saturday. High pressure starts to build in from the SW Sunday, although the gradient between this high and deepening low pressure over the Canadian Maritimes will continue breezy conditions Sunday. && .AVIATION /04Z TUESDAY THROUGH SATURDAY/... Short Term...Another round of valley fog is expected at LEB and perhaps HIE tonight and possibly Tuesday night as well. Otherwise VFR conditions are expected at all other sites through Tuesday. An area of low pressure passing south of New England could bring MVFR ceilings toward MHT and the coastal terminals Tuesday evening along with a few showers for PSM and MHT. However, confidence is on the lower side. Long Term...Low pressure well south of New England will spread cloud cover across the southern third of the area Wednesday and slight chances for showers. VFR will likely prevail Wednesday, although there could be periods of MVFR cigs across southern and coastal terminals. VFR for all is expected Thursday into Friday. A cold front crosses late Friday bringing scattered showers across the interior and potential for MVFR conditions at KHIE and KLEB. As colder air filters into the region late Friday night rain showers may mix with snow at KHIE bring further restrictions. && .MARINE... Short Term... Seas continue to on the slower side to diminish so have extended the SCA for the Stonington to Port Clyde zone through 8PM this evening. The SCA for the southern waters has been extended through Tuesday afternoon but probably will need to go beyond this as northeast winds will start to increase again Tuesday night. Long Term...Low pressure well south of New England will continue steady NE flow Wednesday with SCAs possible due to seas greater than 5 ft. Seas gradually subside Thursday with generally light winds over the waters. Southerly to southwest flow increases Friday ahead of a cold front approaching from the west. SCAs may be needed again late Friday night into Saturday as southerly flow shifts out of the west with gusts up to 25 kts. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...Freeze Warning until 9 AM EDT Tuesday for MEZ012>014-018>020- 033. Frost Advisory until 9 AM EDT Tuesday for MEZ021-022-025>028. NH...Freeze Warning until 9 AM EDT Tuesday for NHZ003>007. Frost Advisory until 9 AM EDT Tuesday for NHZ008>010. MARINE...Small Craft Advisory until 4 PM EDT Tuesday for ANZ152-154. && $$ NEAR TERM...Combs/Cornwell SHORT TERM...Combs LONG TERM...Schroeter
Area Forecast Discussion
National Weather Service Pueblo CO
849 PM MDT Mon Oct 3 2022 .UPDATE... Issued at 843 PM MDT Mon Oct 3 2022 Made a few adjustments to the precipitation chances across the Palmer Divide and far Eastern Plains for the rest of tonight based on the latest radar data and high-res model guidance. Light rain showers will likely prevail through around midnight. Also removed the mention of thunderstorms given the hour and lack of support. Mozley UPDATE Issued at 601 PM MDT Mon Oct 3 2022 Updated precipitation chances across the region for tonight. A band of showers and embedded thunderstorms continues to lift northeast, from a Kim to Eads line. A boundary sitting across the lower Arkansas River Valley also has light showers and embedded thunderstorms. This activity should continue to track eastward this evening. High-res model guidance continues to print out showers and thunderstorms over Teller and El Paso Counties this evening. Radar and satellite imagery has a few light rain showers showing up. Instability is rather weak and have a feeling not much more than light rain will move across this area through the next couple of hours. Mozley && .SHORT TERM...(This evening through Tuesday) Issued at 304 PM MDT Mon Oct 3 2022 Key Message: 1) Little change in the pattern, as occasional showers/thunderstorms will continue overnight and through the day on Tuesday. Currently, showers/thunderstorms have developed on the plains from near Trinidad to Lamar, where low level moisture convergence was maximized along weak surface trough/frontal boundary. Have had a couple small hail reports with the stronger cells back toward Trinidad earlier today, though overall storm intensity has been limited by only moderate instability (CAPE of around 500 J/KG) available ahead of the boundary. Convection has been slower to develop elsewhere across the area this afternoon, as slightly drier air spreading south on the plains behind the front has led to only very low instability (CAPE less than 200 J/KG), while weak subsidence under the right front quad of the upper jet was tending to squash storms over the mountains. For this evening and overnight, upper forcing becomes slightly more favorable for precip formation as right rear quad of the jet moves across and low levels moisten a bit, with most CAMs developing at least scattered convection along the eastern mountain slopes and nrn I-25 corridor through midnight, then pushing some weakening activity onto the plains into Tue morning. Overall, trimmed back pops somewhat over the mountains overnight, where precip will shift eastward by midnight, though most locations will keep at least an isolated mention through the night. On Tuesday, models differ with placement of precip on the plains in the morning, with a handful of fairly wet solutions (12z/18z NAM), while bulk of solutions (HRRR/12z GFS especially) keep surface trough and resultant precip farther east. Forecast splits the difference with scattered pops most areas through midday, highest south of the Arkansas River. By afternoon, mountains, especially along and south of Highway 50, light up with convection, though HRRR and GFS keep heaviest rainfall farther south in NM. Again, pops lean toward a blended solution, with chances most locations and likely pops srn mountains and srn I-25 corridor. Instability not particularly high, so mainly showers with weak isolated thunderstorms will be the precip type. Max temps along and east of the mountains and across the plains should trend downward several degf as cooler air filters into the region, while mountains and valleys remain seasonably cool. .LONG TERM...(Tuesday night through Monday) Issued at 304 PM MDT Mon Oct 3 2022 Key Messages: 1. Scattered rain chances especially in the Palmer Divide and in the southern portions of the County Warning Area. 2. Snow accumulations possible in high elevations above 11000 feet. 3. Possible first cold air event of the season next week throughout the CWA. Tuesday Night and Wednesday Low Pressure trough over Montana will begin its trek eastward, this will draw in moisture from the southwest, causing some upsloping in the southern part of the Country Warning Area and a little in the Palmer Divide. There will be enough moisture and lift to produce scattered showers and embedded thunder. This trough will bring in a cold front Tuesday night into Wednesday morning, and temperatures will be just below seasonal averages, with highs in the 60`s and 70`s in the I-25 corridor and eastward, and in the 50`s and 60`s in the mountains and mountain valleys. Light snowfall at levels above 11000 feet are still possible during the evening hours throughout the forecast period. Thursday through Monday Northwest flow aloft will prevail the next few days, stemming from low pressure trough to the east, and an upper low will form in the desert in the southwest US, enabling more moisture to come into 4 corners area. This could increase rain chances in our CWA ahead of a possible strong cold front moving through the region mid week, which could bring the first cold weather of the season to the plains, mountains and mountain valleys. -Riser && .AVIATION...(For the 00Z TAFS through 00Z Tuesday evening) Issued at 304 PM MDT Mon Oct 3 2022 At KCOS, prevailing conditions will be VFR through the period, with a low risk of brief MVFR cigs as vcsh develops from 22z-05z. Also a small risk of a vcts 00z-03z, though won`t include in the taf at this point. After precip ends, low VFR cigs may hold on for much of the night, before slowly lifting Tue morning. On Tuesday, slight chance of a vcsh/vcts after 21z. At KPUB, VFR the next 24 hrs. Risk of a vcsh this evening after 02z, though cigs/vis should remain VFR into Tue morning. Slight chance of a vcsh/vcts after 22z Tue. At KALS, mainly low VFR cigs into the evening, with a vcsh and perhaps a brief period of MVFR cigs from 21z-03z. Low risk of a vcts as well 22z-01z, though chance still looks too low to mention in the forecast at this point. Precip chances end 02z-04z, though low VFR/brief MVFR cigs may linger through the night into Tue morning. Slight chance of a vcsh/vcts returns Tue afternoon, after 21z. && .PUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...MOZLEY SHORT TERM...PETERSEN LONG TERM...RISER AVIATION...PETERSEN