Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 10/19/21


Area Forecast Discussion
National Weather Service Amarillo TX
632 PM CDT Mon Oct 18 2021 .AVIATION... For the 00Z TAFs: VFR conditions are expected at all three terminals throughout this TAF cycle. The main item of concern for this period will be the potential low level wind shear overnight. A jet around 1,000 to 1,500 ft AGL could reach speeds of 50-60 knots from the south/southwest. Otherwise, we are expecting plenty of sunshine and--at times--breezy winds through the next 24 hours. Guerrero && .PREV DISCUSSION... /Issued 253 PM CDT Mon Oct 18 2021/ SHORT TERM...Tonight through Tuesday Night... Warm and dry conditions expected to continue through Tuesday, prior to a cold front arrival Tuesday night. Upper level trough currently east of the Reno NV area is expected to track towards the Salt Lake area this evening. In general warm and dry southwest flow out ahead of this trough is expected. However, just enough mid level moisture around 600-700mb will be advected over the southern Panhandles later this afternoon to early evening. As a result there might be just enough instability to get a shower/isolated storm to develop. The layer below is pretty dry so doubt there will be much precipitation involved, if anything there might just be some breezy winds out of it as evaporative cooling will take place under the cloud bases. While a couple deterministic models as well as the HRRR model hint at these showers, the confidence still remains low, and thus only a 10 pop isolated rain shower will be noted at this time. Breezy south winds 15 to 25 mph with gusts up to 30 mph will continue through sunset across the Panhandles. Might be just enough for elevated Fire Weather conditions in the Cimarron County area. Winds are expected to stay up overnight and will likely keep the temperature well mixed and limit the radiational cooling. As a result lows tonight look to be in the 50s across much of the area. With the warmer start to the day on Tuesday and continued south to southwest flow highs will likely be in the upper 70s to mid 80s. Most of the moisture should be east of the area on Tuesday and thus do not expect any isolated shower activity at this time. Winds will shift out of the north and a cold front is expected to move through after midnight Tuesday night. As a result morning lows will be much cooler with mid 30s in the northwest and mid to upper 40s in the southeast. Weber LONG TERM...Wednesday through Sunday... Following the cold front Tuesday night, Wednesday will be a bit cooler with temperatures slightly below normal. West northwesterly flow will build in aloft as the low pressure system pushes farther east towards the Great Lakes and a ridge builds into the western CONUS. Temperatures will remain in the 70s through the remainder of the week with mostly light southwest surface winds. Winds may turn to the north briefly Friday morning, but will remain light throughout the day. Saturday, the flow aloft becomes westerly with the GFS/Canadian hinting at a few disturbances in the flow and more southwesterly flow aloft. Along with the disturbances aloft, the GFS/Canadian form a lee low off the Rockies in east central Colorado with breezy southwest winds possible Saturday afternoon through Sunday. Meanwhile, the EC keeps the westerly flow aloft with no surface low formation. If the weak disturbances come to fruition, there is a chance for some light shower activity across the east and southeast Panhandles Saturday night into Sunday. Rutt && .AMA Watches/Warnings/Advisories... TX...None. OK...None. && $$
Area Forecast Discussion
National Weather Service Grand Forks ND
1016 PM CDT Mon Oct 18 2021 .UPDATE... Issued at 1014 PM CDT Mon Oct 18 2021 Wind shift/cold front moving into Brandon MB and into far NW ND. It is moving SSE and track would have wind shift into GFK around 09-10z. Clouds to follow about 2 hours later. Upstream cloud cover and heights are not extensive so far but something to watch as short term models insist on bringing in a larger MVFR deck behind front. More of an aviation issue than public. UPDATE Issued at 701 PM CDT Mon Oct 18 2021 High clouds over the area this evening, but thin. Mild out there after a very warm day. Will be watching cold front drop south- southeast from Canada overnight into Tuesday AM. HRRR has it entering NE ND around 06z and near GFK 09z. && .SHORT TERM...(This evening through Tuesday night) Issued at 321 PM CDT Mon Oct 18 2021 Impacts in the short term will be minimal, though temps much cooler, with a dry cold frontal passage expected to bring much cooler weather to the area tomorrow. A quiet and warm evening will be the last of the warmth for awhile with north winds greeting the morning as gusts behind the front set to be 30 to 40mph based on the Bufkit soundings depicting mixing to 950mb of the 30 to 35kts within the blyr CAA and with pressure rise couplet moving down the valley in the wake of the front offering efficient mixing of the downward momentum transfer. Cloudy and much cooler than today with highs 20 to 30 degrees cooler Tuesday, in the 40s and 50s. Late overnight some light rain will attempt to lift into SE ND with the passage of an upper wave across the central plains with most of any accumulation holding off until Wednesdays time frame, covered in the long term section below. .LONG TERM...(Wednesday through Monday) Issued at 321 PM CDT Mon Oct 18 2021 Highlights of potentially impactful weather within the long term period mainly revolve around the region`s first widespread hard freeze of the season likely (70-90%) starting Wednesday night as a seasonable polar air mass moves over the area. Impacts however are likely mitigated by this event`s late season occurrence. A progressive Colorado low is still favored to move into the Central Plains of SD/NE east into the Upper Midwest of MN/IA/WI Wednesday. This track slides the northern deformation zone precip shield across southern portions of the FA, with the southern Valley into west-central MN favored for most precip. While there is some signal for maybe some fgen, the overall progressive nature of the low and generally lower amount of available moisture content will limit amounts to the 0.10-0.50 inch range, with some higher amounts in smaller locations likely given signal for fgen within the def zone forcing. Temps are currently forecast to be warm enough to negate general concern for ptype issues, in addition to the precip zapping effects of expected very dry air filtering in behind the low. However, there still may be just enough overlap towards the northern and western edge of the precip shield to mix in some snow flakes, however no impacts are expected given very light amount of snow (if any) and warm ground temps. The seasonably cold, polar air mass behind Tuesday`s cold front continues into the Northern Plains fed by northwesterly flow behind the exiting Colorado low, with even perhaps a backdoor cold front its parent upper low into the Great Lakes region late in the week to reinforce this colder air. This air mass along with favorable synoptics to promote radiational cooling within a very dry air mass are driving the likely chances of temperatures at or below 28 degrees during the overnights and mornings of Wed night- Sat morning. While this isn`t unusual for this time of year, it is the region`s first widespread coverage and multiple days of hard freeze criteria. Given such a late occurrence in this fall season, area agricultural impacts should be mitigated, or rather not unexpected. Getting into next week, clustered ensemble guidance hints at more upper ridging which may help bring temps back to above seasonal averages. NBM is picking up on this with 75th percentile high temps back into the 60s for some locations within the FA. && .AVIATION...(For the 00Z TAFS through 00Z Tuesday evening) Issued at 701 PM CDT Mon Oct 18 2021 After several days of clear weather, will watch cold front drop south across the area late tonight into Tuesday. Short term models all bring a deck of MVFR cigs southward behind the front 1-2 hours after passage. From satellite however, that would seem fast. But short term models have done pretty well in the past with these lower clouds moving in so left its thinking for the TAFs. Gusty north winds 20-30 kts Tues esp E ND/NW MN, much less BJI-FFM areas which will hold onto the south winds into the aftn. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...None. MN...None. $$ UPDATE...Riddle SHORT TERM...JK LONG TERM...CJ AVIATION...Riddle
Area Forecast Discussion
National Weather Service Gray ME
1108 PM EDT Mon Oct 18 2021 .SYNOPSIS... Upper level low will continue chances for showers primarily in the mountains through Tuesday. Above normal temperatures return Wednesday into Friday followed by another cool down over the weekend. Chances for widespread precipitation through the end of the week are low as the next low pressure system passes to our northwest. There will be chances for showers across the north Thursday with a warm front with additional chances Friday with the passage of a series of cold fronts. && .NEAR TERM /UNTIL 6 AM TUESDAY MORNING/... 1105 PM Update... Have trended temperatures and dew points lower in the forecast this evening. Webcams and surface observations from northern New Hampshire indicated some snow across the higher terrain late this evening. Have also upped pops for the next couple hours per latest radar imagery and the latest HREF and HRRR solutions across northern areas. Otherwise, just minor adjustments to winds across the forecast area. 615 PM Update... Made some adjustments to PoPs based on radar imagery and near- term forecast guidance such as the HRRR and HREF. The convergence band of rain that has been over portions of extreme southeastern Cumberland county and York county, ME continues to move offshore and weaken. The expectation is that areas south of the mountains will begin to clear out as these showers end but across the north and mountains additional upslope rain and snow showers will continue through the overnight. Other than some minor adjustments to temperatures, dewpoints, and sky cover the rest of the forecast remains on track. Previously... Northwesterly flow around an upper level low to our northeast is dominating the weather this afternoon. This has resulted in generally widespread cloud cover, with the exception of downwind of the higher peaks where we see some clearing. Showers are widespread across the higher terrain, with rain at lower elevations and snow on the summits both being observed. Downwind of the mountains a nice convergence pattern has also resulted in some enhanced showers into York county ME. Through evening, expect much of the showers to decay as they are supported by mostly diurnal instability. With that clearing temperatures across the coastal plain will drop rapidly under clear skies, and expect pockets of frost to develop, which could be the first of the season for some of these areas. Further north the mountains will also see temps drop into the mid 30s but with cloud cover. && .SHORT TERM /6 AM TUESDAY MORNING THROUGH TUESDAY NIGHT/... Tuesday will see a continuation of the NWly flow, although not quite as windy as today as the pressure gradient and upper level low moves off to the east. A few gusts to 20mph are possible. Again expect a diurnal increase in showers across the high terrain, with rain the valley and snow on the summits. While the overall QPF amounts are quite light the continued upslope flow will amount to a few inches of snow accumulations on the peaks. && .LONG TERM /WEDNESDAY THROUGH MONDAY/... The extended forecast period will start out with northern New England on the northeast periphery of a surface high over the SE CONUS with a belt of strong northwest flow aloft exiting the region into the Atlantic. Ridging aloft will build in on Thursday followed by an area of low pressure passing to our NW through Quebec. The bulk of the precipitation with this area of low pressure is projected to pass to our NW, although a series of cold fronts will cross the area Thursday night into the weekend. These cold fronts will bring chances for showers along with reinforcing shots of cooler air. Temperatures will start the period above normal Wednesday into Friday followed by temperatures dropping below normal Saturday into early next week. Wednesday will mark the beginning of a stretch of warmer weather after a cool start to the week. Temperatures will climb into the upper 60s to near 70F across southern areas with 50s for high across the north. A departing belt of strong mid to low level winds may lead to a fair amount of clouds to start with clearing skies in the afternoon. An inversion will keep strong winds associated with the enhanced mid to low level flow from reaching the lower elevations although winds will be quite strong in the mountains. Wednesday night into Thursday low pressure will be taking shape over the Great Lakes while ridging aloft crests over New England. This low will lift a warm front through the area Thursday with models suggesting precipitation will be limited with this front. Temperatures will be slightly warmer Thursday than Wednesday with partly to mostly cloudy skies. Thursday night through Friday low pressure will be tracking through the St Lawrence Valley. Current guidance suggest that this low will drag a couple cold fronts through the area Friday into Saturday with organized precipitation along the fronts washing out as they approach the area. Thus, prospects of widespread precipitation are low with some areas downstream of the mountains likely not seeing any precipitation through the forecast period. Cooler weather is expected over the weekend withs high relegated to the 50s and 40s by Sunday. && .AVIATION /03Z TUESDAY THROUGH SATURDAY/... Short Term...MVFR will hold through the mountains over the next 24 to 36hrs as NWLy upslope continues. Snow showers aloft and Rain showers in the valleys will be most widespread late afternoon and wane with the sun. Elsewhere partly sunny skies with VFR continuing under NWLy flow. Long Term...Mainly VFR is expected Wednesday through the end of the week. Low pressure passing through Quebec may bring periods of MVFR Thursday night into Friday. && .MARINE... Short Term... Winds and seas will be low SCA thresholds Wednesday into Thursday. Southerly winds ahead of a series of cold fronts may approach SCA criteria Thursday night into Friday. Long Term... NWly flow will persist for the next few days with marginal SCA conditions continuing. Best chance for strong winds will be tonight as the pressure gradient && .GYX WATCHES/WARNINGS/ADVISORIES... ME...None. NH...None. MARINE...Small Craft Advisory until 8 PM EDT Tuesday for ANZ150-152-154. && $$ Cannon/Tubbs
Area Forecast Discussion
National Weather Service North Platte NE
631 PM CDT Mon Oct 18 2021 .SYNOPSIS... Issued at 347 PM CDT Mon Oct 18 2021 H5 analysis from earlier this morning had a closed low just north of Reno Nevada. A trough extended south of this feature into southern California. Downstream of this feature, ridging extended from the Ozarks north into western Ontario. Downstream of this feature, closed low pressure was noted over eastern Quebec with a trough extending south into New England. At the surface, a weak surface trough was present from sw Nebraska south into sern Colorado. Winds across central and eastern Nebraska were gusty this afternoon, while lighter winds were present along and west of highway 83. Skies were partly cloudy in the west and mostly clear in the east this afternoon and 2 PM CT temperatures ranged from 63 degrees at Imperial and Ogallala to 77 degrees at Valentine. && .SHORT TERM...(This evening through Tuesday night) Issued at 347 PM CDT Mon Oct 18 2021 The main forecast challenge will be precipitation and weather impacts with the approaching H5 low (currently near Reno Nevada). This feature will track east, approaching far northwestern Colorado by 12z Tuesday. Downstream of this feature, surface low pressure will quickly deepen over northeastern Colorado. Winds will increase east of this feature, leading to a fairly mild night across the area. With the combination of winds and increasing high cloudiness, lows will be in the lower to middle 40s. The upper level low will track east, approaching the western Nebraska panhandle by 00z Wednesday. Downstream of this feature, surface low pressure will track into central Nebraska at the same time. A strong cold front will be oriented south to southwest of this feature with a warm front extending northeast of the low. An inverted surface trough will extend north of the low into north central Nebraska and central South Dakota by 00z Wednesday. Light precipitation will develop in the northwestern forecast area Tuesday afternoon as isentropic lift increases quickly across northwestern Nebraska. Temperatures will remain warm enough to support all liquid precipitation thorugh 00z- 03z time frame. Temperatures do cool enough to support all snow in the northwest after 03z, however, isentropic lift will lift quickly north into South Dakota by late evening, shifting the bulk of pcpn north of the area. One caveat here however, is the 12z nam soln from this morning. It develops some convective pcpn along the NE/SD border late Tuesday evening. If that were to come to fruition, we could see a quick burst of convective snow along the border mid to late evening Tuesday. This is advertised by the NAM12 soln, however it is not advertised in the GFS soln. The HRRR soln from 12z this morning develops some convective elements just over the border into South Dakota. With the bulk of broad scale isentropic lift being north of the area during the late evening and overnight hours, not anticipating much in the way of snow accums. Tuesday night. For now, I have a stripe of 1 to as much as 2 inches of snow in the Pine Ridge of northern Sheridan and far northwestern Cherry county. Another aspect keeping snow accumulations on the lower end are SLR ratios which are running in the 5 to 7 inch range. Further south and east, we could see a skiff of snow, however, almost all pcpn should fall as rain as temperatures remain in the middle to upper 30s through 09z Wednesday. As mentioned earlier, isentropic lift will shift north of the area by late evening, bringing a quick end in precipitation over north central Nebraska overnight. .LONG TERM...(Wednesday through Monday) Issued at 347 PM CDT Mon Oct 18 2021 Temperatures will be very chilly on Wednesday behind the exiting system. H85 temps will range from -3C in the north to 6C in the southwest. Highs will struggle to get out of the lower 40s in far northern Nebraska where persistent cloud cover is expected, while highs will reach into the lower 50s mainly south of I-80. Temperatures will slowly begin to moderate upward to more seasonal levels toward the end of the week. Northwesterly flow aloft will persist through Friday, followed by a ridge building east of the Rockies Saturday into Sunday. Highs will be mainly in the 60s toward the end of the week with some lower 70s possible in SW Nebraska Sunday and Monday. && .AVIATION...(For the 00Z TAFS through 00Z Tuesday evening) Issued at 631 PM CDT Mon Oct 18 2021 VFR is expected throughout wrn and ncntl Nebraska tonight and Tuesday morning. Thereafter, a storm system over the cntl Rockies this evening will begin spreading MVFR/IFR conditions in -RA and low ceilings across wrn Nebraska affecting areas north of highway 2 and west of highway 83 (Sheridan and western Cherry counties). VFR is expected elsewhere during this time. && .LBF WATCHES/WARNINGS/ADVISORIES... None. && $$ SYNOPSIS...Buttler SHORT TERM...Buttler LONG TERM...Buttler AVIATION...CDC
Area Forecast Discussion
National Weather Service Portland OR
319 PM PDT Mon Oct 18 2021 .SYNOPSIS...After a brief break in the wet weather through Tuesday, expect a very active weather pattern to bring valley rain and high mountain snow every 12-24 hours through early next week. && .SHORT TERM...THIS EVENING THROUGH THURSDAY...Clouds have been slow to erode in the southern Willamette Valley and Cascades so far this afternoon, and it`s doubtful whether they`ll clear before the day`s over, but the radar remains clear and observations have been coming in dry across the board the past several hours. The next timeframe that area-wide rain will be likely begins tomorrow evening. Between now and then, on the back side of the cut-off low that brought rain to parts of the region yesterday, the overall pattern is tranquil in nature, with weak pressure gradients that will favor light winds. The area is likely to be cooler than normal today with highs generally in the 50s across the board in the lowlands. It will be a little warmer tomorrow in warm air advection ahead of the next approaching trough, though there is some uncertainty in how warm due to uncertainty in how cool it will get tonight. Sky guidance is overwhelmingly indicative of clearing late this evening through the overnight, with hints that radiational fog and/or low stratus will develop in the early morning - mainly across the central and western Willamette Valley. If this does occur, the very presence of fog would imply maximum surface cooling overnight - with temperatures falling to the dewpoints (currently forecast to be in the 30s early tomorrow morning) in a layer at/very near the surface. But then the fog/low stratus itself could hinder surface heating for part of the day, depending on the depth of this saturated layer (the deeper it is, the longer it takes for the sun to "burn" it off), and a later burn off time means surface heating starts later; this, in turn, means that there is less time for the surface to heat before the sun begins to go down and outgoing longwave radiation from the surface becomes greater than the incoming shortwave that it`s receiving; all this is to say forecasting tomorrow`s high is tricky. What`s a little easier is assessing the time of arrival for precipitation, which looks to arrive first in the Florence area during the 4-7 PM timeframe tomorrow before quickly overspreading the remainder of the area over the successive several hours. A weak surface low will then move along the coast, dragging with it a cold front that will bring an end to the steady rain and introduce a threat for showers - especially along the coast and in the Coast Range - Wednesday. NBM continues to suggest the possibility of thunder over the waters Wednesday morning, and the SREF doesn`t disagree, so for now that has been left in the forecast. The low will also yield some gusty winds Wednesday morning. As is usually the case in these scenarios, the coast and Coast Range will receive the brunt of the impact from these gusty winds, but the interior lowlands and even the Cascade Foothills are looking gusty too. The latest runs of the HRRR and ARW are suggestive of gusts to around 35 to 40 mph (perhaps higher in spots) in the southern and central Willamette Valley, 40 to 45 mph in the Coast Range and Cascade foothills, and 45 to 50 mph along the shoreline (with gusts in the high Cascades at least that high). For now, the forecast is a conservative blend of high resolution models, but it could certainly be a bit gustier if the higher end of guidance shakes out. The most favored timeframe for a break in precipitation looks to be late Wednesday evening through around lunchtime on Thursday. Thursday evening an occluded front from the bombed out low in the Gulf of Alaska nears the area to bring another round of widespread, gentle rain to all of NW Oregon and SW Washington from Thursday evening through Friday night. -Bumgardner .LONG TERM...FRIDAY THROUGH SUNDAY...If the ECMWF and GFS are right, the deep cut-off low in the Gulf of Alaska gets picked up by another upper trough swinging down from the northwest, and subsequently merges with another surface low which will bring in another cold/occluded front during the Saturday/Saturday night time period. Ahead of the front, the area should experience another round of rain; behind it, the pattern turns showery again. Forecasting becomes exceptionally difficult beyond Saturday, as the pattern stays active, but each ensemble member seems to have a different depiction of the placement and strength of any storm system to approach our area on and beyond Sunday. In the left exit region of a ~150 knot 200-300mb jet extending across central/ northern CA into northern NV, strong cyclogenesis is possible in/near the Pacific Northwest and the adjacent eastern Pacific between Saturday night and late Monday. If an intense enough system can approach our area with the proper orientation of its pressure field, a high wind event could unfold, but given the model disparities at this time range it just wouldn`t make sense to make consequential changes to what the NBM has populated in its forecast. Models` forecasts of dynamic processes favored for cyclogenesis (including 500mb vorticity advection; thermal advection; adiabatic cooling and heating due to vertical motions; diabatic heating and cooling provided by earth`s surface, solar heating, and latent heat release by condensation in clouds; etc.) will be analyzed in the coming days to determine whether anything consequential will arise from this pattern. -Bumgardner && .AVIATION...Dry southerly flow aloft as high pressure builds across the region. Generally broken lower VFR clouds are expected to clear by 02Z this evening according to HREF guidance. VFR conditions will likely persist through the period ending 00Z Wednesday. Light offshore flow develops tonight so may see patchy fog in the valley later tonight. MOS guidance suggests most likely locations for brief IFR conditions will be at KEUG, KSLE, and KHIO between 10Z-15Z Tuesday. For detailed regional Pac NW aviation weather information, go online to: https://weather.gov/zse KPDX AND APPROACHES...VFR to prevail through Tuesday afternoon. Light onshore flow will turn easterly around 04Z Tuesday. /DH && .MARINE...High pressure will push inland tonight with winds becoming southeasterly across the coastal waters. A strong front will approach the region later Tuesday into Wednesday. Expect winds to gradually increase ahead of the front overnight. Winds will continue to increase Tuesday as the front enters the coastal waters with a period of Gale force winds expected mainly for the outer waters Tuesday afternoon through Tuesday night. The strongest wind is expected west of about 35 NM. Expect periods of enhanced southerlies to then persist through the end of the week as another front moves through the waters Thursday into Friday. Meanwhile, seas will be dominated by a decaying westerly swell through the beginning of the week as it subsides from around 10 feet this afternoon to 5-6 feet on Tuesday morning. The next front will bring an uptick in short period seas Tuesday into Wednesday, peaking around 12 ft nearer to shore and 20 feet beyond 35 NM early Wednesday. Seas settle some later Wednesday to around 8 to 10 ft as a fresh westerly swell arrives. DH/MH && .PQR WATCHES/WARNINGS/ADVISORIES... OR...None. WA...None. PZ...Small Craft Advisory from 11 PM this evening to 11 AM PDT Tuesday for coastal waters from Cape Shoalwater WA to Florence OR from 10 to 60 nm. Gale Warning from 11 AM Tuesday to 5 AM PDT Wednesday for coastal waters from Cape Shoalwater WA to Florence OR from 10 to 60 nm. Small Craft Advisory from 8 PM Tuesday to 5 PM PDT Wednesday for coastal waters from Cape Shoalwater WA to Florence OR out 10 nm. $$
Area Forecast Discussion
National Weather Service Pueblo CO
941 PM MDT Mon Oct 18 2021 .UPDATE... Issued at 934 PM MDT Mon Oct 18 2021 Given recent trends, have decided to issue a High Wind Warning for the southern Sangres for late tonight through midday Tuesday. Previously mentioned mountain wave setting up tonight should yield southerly gusts up to around 75mph later tonight, with HRRR continuing to show this possibility at this time. Would not be surprised to see a few higher gusts to 80-85mph Tuesday morning, before winds diminish by late morning into midday. UPDATE Issued at 715 PM MDT Mon Oct 18 2021 Update this evening was to expire the Red Flag Warning which was in effect for eastern Huerfano, Las Animas and Baca Counties. Gusts may continue this evening, though RH values will continue to improve. A Red Flag Warning remains in effect from Noon until 7 PM MDT Tuesday for strong winds, low relative humidity and dry fuels, that includes Fremont, southern El Paso, Pueblo, Huerfano, Las Animas, Crowley, Otero, Bent, Prowers, Kiowa and Baca Counties. && .SHORT TERM...(This evening through Tuesday) Issued at 306 PM MDT Mon Oct 18 2021 ...Critical Fire Weather Conditions on the Plains Tuesday... Upper level low moving through the Great Basin this afternoon, while lee surface trough deepens on the plains. Tightening pressure gradient and deeper mixing ahead of the low have led to gusty winds across much of the area, with patchy Red Flag Conditions along the Raton Mesa eastward into Baca County. Upper low moves quickly eastward into nwrn CO overnight, then pushes eastward along the CO/WY border through the day Tue. Models suggest brief band of snow showers spreading across the Continental Divide toward 12z as main lift with the low/trough comes across, then mainly scattered snow showers through the day Tue, especially in nw flow enhanced locations in Lake County around Leadville/Fremont Pass. Not expecting much more than a dusting to an inch of snowfall across most of the Divide, though higher peaks of the Sawatch could see an inch or two if they`re lucky. Surface winds over much of the area will remain breezy overnight, with perhaps some strong gusty winds in the lee of the eastern mountains, especially the srn Sangres, where HRRR shows some gusts over 50 kts, as brief mt wave sets up 09z-15z before forward shear increases by late morning. For Tue, upgraded the Fire Weather Watch to a Red Flag Warning, as deep mixing and increasing downward vertical motion should enhance winds along and east of the mountains through the day, while dewpoints drop off into the teens, which should more than offset any cooling in surface temps. Maxes should end up about 8-10 degf cooler at most locations as mid level temps fall behind the departing upper trough. .LONG TERM...(Tuesday night through Monday) Issued at 306 PM MDT Mon Oct 18 2021 Tuesday night...The upper low pressure system will be exiting the region Tue night, producing some lingering snow showers over the central mts through around midnight, as well as push a weak cold front south across the state during the overnight hours. Additional snow accumulations of up to an inch are expected as the shower activity wanes. Expect minimum temps overnight to drop into the 20s to around 30F for the high valleys, teens for the heart of the San Luis Valley, and 30s across the plains. Wednesday through Saturday...The story for the rest of the week and into the weekend is a ridge of high pressure, producing dry conditions, lighter winds and warming temps. Overnight low temps are forecast to be in the 20s to around 30F for the high valleys, and 30s to around 40F for the plains. Highs will be slightly cooler for Wed due to the cold front, in the upper 50s and 60s for most areas, then 60s for the high valleys and 70s for the plains for Thu through Sat. Sunday and Monday...Long range models are still indicating a Pacific longwave trough will move onshore over the weekend, approaching the region and introducing some isolated pcpn chances along the Continental Divide starting Sunday. There are some timing and strength differences between models, so confidence is low at this time on what this next pattern shift will actually mean for south central and southeast Colorado. Stay tuned. Moore && .AVIATION...(For the 00Z TAFS through 00Z Tuesday evening) Issued at 306 PM MDT Mon Oct 18 2021 VFR at all taf sites the next 24 hrs. S-SW winds will gust 20-25 kts into the evening at all terminals, then decrease slowly after sunset. W-SW winds will increase again Tue morning at all sites, with gusts 20-25 kts from mid-morning into the afternoon. && .PUB WATCHES/WARNINGS/ADVISORIES... Red Flag Warning from noon to 7 PM MDT Tuesday for COZ222- 227>237. High Wind Warning from 3 AM to noon MDT Tuesday for COZ074-075. && $$ UPDATE...RODRIGUEZ SHORT TERM...PETERSEN LONG TERM...MOORE AVIATION...PETERSEN