Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 10/31/17


Area Forecast Discussion...UPDATED
National Weather Service Corpus Christi TX
916 PM CDT Mon Oct 30 2017 .DISCUSSION... Tonight. A cold front...currently located just north of the Hill Country...is prog to slowly shift south overnight with the western extent sliding down the Rio Grande by sunrise. Before then, weak SE llvl flow this evening should eventually become more ENE by late in the night across all but the immediate coastal areas as the boundary pushes south across the Brush Country. Tuesday. Boundary is prog to stall across the Brush Country in the morning and then slowly crawl eastward through the day and transition into a strengthening inverted sfc trough. How far east the boundary makes it in the afternoon is up in the air. GFS keeps the boundary across the Brush Country for most of the day...the ECMWF is even farther west...the NAM farther east...and the RAP takes it offshore...with the NMM/TTU WRF/ARW/NSSL WRF all over the place as well. Where the boundary ends up will have a significant impact on how much precip the area sees during the day. Areas to the east of the boundary will have the greatest chances of rain Tuesday as WAA redevelops as weak low pressure may try to develop along the boundary. The GFS and NAM both want to increase PWATs to 1.9 to 2" across the coastal counties by late in the day which is about +2 Sigma for this time of year. Strengthening/transitioning troughing will aid in shower development in the morning (especially Coastal Plains) with a possible increase in coverage occurring in the afternoon as a mid level s/w trough advects east across TX and as an 80kt H25 jet nudges east across S Central TX. Although best dynamics will be to the north of S TX...sufficient large scale lift combined with some daytime heating and a steep llvl boundary should result in convective development in the afternoon. Best chances of convection will again be to the east of the aforementioned boundary (Coastal Plains/Counties) where SBCAPE values of around 1500 j/kg are prog to exist. I am a little concerned about a brief spin-up/tornado being possible in the afternoon across the coastal counties. Although llvl shear values are prog to be weak for most of the day, shear values should strengthen some during the mid to late afternoon hours along with a greater veering of winds aloft...and associated increase in curvature in hodographs. Take these factors and add in an increasingly moist airmass and you can often get a weak tornado or two occurring across the coastal counties of South Texas. An isolated strong wind gust may also occur with any storms that develop. Small hail will be possible...but high freezing and WBZ levels should preclude much if any large hail. Farther west...areas of drizzle/light rain or possibly a shower can be expected to the west of the boundary where isentropic lift should develop. Boundary should continue to shift east Tuesday evening and night with rain chances eventually shifting E/NE. Any tornado threat should diminish in the early evening as instability wanes...but an isolated strong wind gust threat may briefly persist. Overall changes to inherited forecast were to adjust POPs some to account for timing/placement of best/greatest precip chances for Tuesday afternoon/evening. Also adjusted wind speeds some to nudge the front/boundary a little closer to the coast by late in the day Tuesday. Also lowered min temps by a couple of degrees for inland areas tonight as some area are already at previously forecast lows. && .PRELIMINARY POINT TEMPS/POPS... Corpus Christi 66 79 66 80 70 / 20 70 80 40 10 Victoria 61 78 63 81 68 / 20 60 80 40 10 Laredo 63 72 61 81 66 / 10 40 30 10 0 Alice 64 79 64 83 68 / 10 60 70 20 10 Rockport 67 78 68 79 72 / 20 70 80 50 10 Cotulla 60 73 58 82 65 / 10 40 40 10 10 Kingsville 65 80 65 82 70 / 10 70 70 20 10 Navy Corpus 70 79 69 78 74 / 20 70 80 50 10 && .CRP WATCHES/WARNINGS/ADVISORIES... TX...None. GM...None. && $$ HART/79...UPDATE
Area Forecast Discussion
National Weather Service Cheyenne WY
857 PM MDT Mon Oct 30 2017 .UPDATE... Issued at 851 PM MDT Mon Oct 30 2017 Updated this evening and tonight to include areas of fog across the southern Laramie Range between Laramie and Cheyenne. Current webcams show these locations in and out of fog over the past hour, with similar conditions expected through early Tuesday morning. In addition, high res models are now showing a band of light snowfall over the I-80 corridor from Elk Mountain/Saratoga area eastward into Cheyenne and the southern NE panhandle late tonight and Tuesday morning. This is a bit further north than previous forecasts which showed this snowfall mainly across Colorado. HRRR and nam show similar solutions, so decided to increase POP along and south of I-80 tonight. If this band of snow does develop this far north, will have to closely monitor snowfall rates since slick roadways are possible. && .SHORT TERM...(This evening through Wednesday) Issued at 134 PM MDT Mon Oct 30 2017 Mostly clear night expected tonight as surface high pressure slides just to our east. Winds will die especially over the Panhandle where optimal radiational cooling will take place. Temperatures will fall into the upper single digits to lower teens from Alliance to Chadron overnight. Weak southerly return flow will set up early Tuesday which will allow some lower cloud cover to occur roughly from Laramie to Sidney and should limit temps in these areas from bottoming out. After a mostly sunny and warmer day on Tuesday, things get much more active again starting Tuesday night and lasting through Wednesday. 140kt NW`ly upper jet dives south into northern Wyoming Tuesday night. Associated shortwave energy will amplify over the northern plains on Wednesday morning. A 994 mb low will form over eastern MT on Tuesday night and pressure falls associated with this developing low and significant lee troughing will tighten low level gradients significantly. CAG-CPR gradients are quite impressive, peaking near 91 meters per the NAM on Wednesday morning. Additionally, forecast soundings show winds as high as 75 kt down to 3000ft AGL by late Tuesday night in and around the Laramie Range. Issued a High Wind Watch for the wind prone areas of SE Wyoming starting Tuesday evening and lasting through Wednesday. Based on the impressive gradients, subsidence in the right entrance region of the upper jet, and 700 mb winds between 65-75kt, think wind gusts of 80 mph not out of the realm of possibility in the gap areas. For elevations down to around 5000ft, issued a high wind watch for Wednesday as well. Forecast soundings show most places mixing to at least 5000ft AGL during the afternoon which should be plenty high enough to tap into the very fast low level flow. .LONG TERM...(Wednesday night through Monday) Issued at 134 PM MDT Mon Oct 30 2017 Gradients will slowly weaken on Wednesday night as a cold front sags slowly south into our northern counties. Some differences in timing of the front and just how far south it comes. Should the front hang up to the north for a longer time, could see the wind event continue a bit longer. Weak shortwave energy will track east just to our north through Thursday night in fast zonal flow aloft. Lots of timing/placement differences in regards to individual waves. For now, think the best chance for a period of light snow will be over our northern counties, roughly north of a line from Douglas to Chadron. At this time, not expecting significant accumulations. Upper flow turns SW on Friday as significant troughing develops over the NW US. The weekend looks unsettled with the potential for a couple of windy days and possibly some mountain snow. && .AVIATION...(For the 00Z TAFS through Tuesday afternoon) VFR conditions expected for most locations tonight. South to southeasterly flow will develop tonight around KLAR, KCYS, and KSNY after 06z, resulting in some lower CIGS between 06z and 14z early Tuesday morning for these locations. MVFR/near MVFR conditions are expected with brief IFR CIGS possible, especially at KCYS and KSNY. && .FIRE WEATHER... Issued at 134 PM MDT Mon Oct 30 2017 It will be dry and windy through Wednesday along with a gradual warming trend. RH values will remain 20 percent or higher on Tuesday but there may be some elevated conditions on Wednesday afternoon in the immediate lee of the Laramie Range. A weak cold front will cool temps and raise RH values by Thursday. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...High Wind Watch from Tuesday evening through Wednesday afternoon for WYZ106-110-116-117. High Wind Watch from Wednesday morning through Wednesday afternoon for WYZ101-104-105-107-109-115-118-119. NE...None. && $$ UPDATE...TJT SHORT TERM...DEL LONG TERM...DEL AVIATION...TJT FIRE WEATHER...DEL
Area Forecast Discussion
National Weather Service Austin/San Antonio TX
657 PM CDT Mon Oct 30 2017 .UPDATE... 00Z Aviation Update Below. && .AVIATION... VFR conditions under clear skies prevail early this evening. A cold front just north of the region early this evening will enter portions of the Rio Grande and Hill Country 02Z-04Z and to the I-35 corridor roughly around 06Z. A wind shift to the N around 5-10 kts will initially occur and then stengthen slightly Tuesday morning. Behind the front isentropic upglide will develop across South Central Texas overnight in response to an approaching mid and upper level low. As a result stratus will develop over the frontal airmass 06Z-09Z from south to north. There are some differences between the GFS, NAM12 and HRRR with strength of upglide and how low the moistening and stratus develop. Experimental and operational runs of the HRRR are now indicating some IFR ceilings possible along the escarpment near SAT along with patchy -RA by 12Z with lower end MVFR ceilings now elsewhere, and is also support by NAM12 forecast soundings. The GFS is still indicating higher end MVFR ceilings and less in the way of patchy -RA. Have trended the forecast toward the lower end MVFR ceilings, but not quiet as low as the NAM12/HRRR at the moment. Later Tuesday afternoon and evening elevated SHRAs and isolated TSTMs will be possible. && .PREV DISCUSSION... /ISSUED 259 PM CDT Mon Oct 30 2017/ SHORT TERM (Tonight through Tuesday Night)... Main weather focus is centered on the increasing rain chances for Halloween (Tuesday) afternoon and evening. Showers and a few isolated thunderstorms could occur during the afternoon and into the evening/overnight hours along and east of the U.S. 281 corridor and especially along and east of I-35. While no weather hazards are expected, with many outdoor planned activities, caution is advised as some thunderstorms and pockets of moderate rain could make certain activities more vulnerable to impact. Current water vapor and RAP analysis depict dry air over the region with a modestly strong shortwave trough over southern California and a long-wave trough across the Great Lakes. The surface high pressure system in the Gulf of Mexico is aiding low-level south flow with the initial hint of moisture return to the area. However, this south flow will be short lived as the trough across the Great Lakes region will shift a cold front into the area overnight. The temperature and dewpoint gradient will increase right over the region (frontogenesis) early Tuesday morning. Cooler, denser air will filter south through the day Tuesday yielding abundant cloud cover and cooler conditions. Given the shallow nature of the front, the 925-850mb flow remains south to southwest yielding isentropic upglide lift. Greater saturation of the low levels coupled with this lift looks to best align by Tuesday afternoon. With limited upright instability, general showers are mostly expected during the afternoon. However, as evening approaches, greater amounts of dynamic lift will overspread the region as the shortwave, now over CA, swings across Texas 24-30 hours from now. The combination of the upglide plus the dynamic lift could result in a few pockets of moderate showers and isolated thunderstorms along and east of U.S. 281 halloween evening. Have placed the highest rain chances 50-80% along and east of the I-35 corridor during this time frame. As the shortwave trough passes through Texas by early Wednesday and with lift decreasing, shower coverage will reduce. The front will initially slide south of the region Tuesday but by Wednesday slide back north as a warm front, allowing for moist and warmer air to return. LONG TERM (Wednesday through Monday)... No large highlights in the long-term outside the above normal temperatures expected through the late week and weekend with limited to no rain chances expected through Monday. Some high temperature records could be challenged late week as we return to a warm pattern. The front will shift back north over the region Wednesday and dissipate as near H5 zonal flow occurs across south-central Texas. Dewpoints are projected across multi-model guidance to increase back into the 60s by Thursday. A briskly moving shortwave will traverse Texas and act to sharpen a temperature/dewpoint gradient Thursday but sounding analysis shows a stout cap in place and likely should keep showers/storms at bay across the region. For Friday through the weekend, a weak sub-tropical H5 ridge will develop over north Mexico into south Texas and help aid south to southwest mid-level flow. This warm pattern will drive temperatures up to near record levels in the upper 80s to low 90s. A pattern change looks to be on the horizon early to mid next week but models are not fully in agreement on front or trough strength. && .PRELIMINARY POINT TEMPS/POPS... Austin Camp Mabry 53 66 53 81 64 / 20 50 70 10 - Austin Bergstrom Intl Airport 52 68 53 80 63 / 20 50 70 10 - New Braunfels Muni Airport 53 69 54 81 62 / 20 50 70 10 - Burnet Muni Airport 48 58 48 81 60 / 10 50 50 - - Del Rio Intl Airport 52 63 49 81 58 / - 40 10 - - Georgetown Muni Airport 50 63 52 80 62 / 20 50 70 10 - Hondo Muni Airport 52 70 53 83 59 / 10 50 50 - - San Marcos Muni Airport 52 69 54 81 62 / 20 50 70 10 - La Grange - Fayette Regional 55 71 57 80 65 / 20 50 80 10 10 San Antonio Intl Airport 55 69 56 83 63 / 20 50 60 - - Stinson Muni Airport 56 71 56 82 63 / 20 50 60 - - && .EWX WATCHES/WARNINGS/ADVISORIES... None. && $$ Mesoscale/Aviation...Runyen Synoptic/Grids...05 Public Service/Data Collection...YB
Area Forecast Discussion
National Weather Service Jackson MS
919 PM CDT Mon Oct 30 2017 .UPDATE... Updated for evening discussion. && .DISCUSSION... Expect mostly clear skies overnight with low temperatures mainly in the low to mid 40s. The current forecast is in good shape with no changes needed. /27/ Prior discussion below: Tonight and Tuesday... Latest RAP and satellite analysis has a longwave trough over the Northern Plains through New England with an associated low centered over southeast Canada. The ArkLaMiss remains beneath southern stream zonal flow aloft with a closed cold core upper-level low over the Desert Southwest. At the surface, a dry and weak cold front was analyzed over central Arkansas and was slowly making its way southeast towards the CWA. This front is progged to enter the Delta around 6z and then stall in the vicinity of the I-20 corridor before slowly lifting back north during the day on Tuesday. Calm winds, clear skies, and large dewpoint depressions ahead of the front will allow for efficient radiational cooling with cold air advection behind the front across the Delta. This will allow overnight min temps to drop into the low to mid 40s across much of the region. On Tuesday, while the northern stream remains amplified with cyclonic wave breaking over eastern Canada and anticyclonic wave breaking over the northeast Pacific, the ArkLaMiss will continue to remain entrenched beneath the zonal southern stream flow. The aforementioned upper-level low over the Desert Southwest will become an open shortwave trough as it quickly propagates through Central Texas towards the area, however precip chances will remain west of the region through the day on Tuesday. The forecast will be centered around the high temps as the stalled front hangs up along or just north of I-20 and cloud cover fills in from the southwest across the Delta. This setup will allow for a very noticeable temperature gradient across the CWA with highs in the low to mid 60s on the north side of the front/Hwy 82 corridor while much warmer temps in the low to mid 70s will be common place along and south of I-20. /TW/ Wednesday through the weekend: A shortwave in Texas will begin to shift eastward overnight Tuesday into Wednesday forced by an upper jet streak moving quickly through the South. This disturbance will bring showers into the CWA early Wednesday. Low level flow out of the south will be gusty and dewpoints will be on the increase going into the afternoon hours. The Euro shows an area of focused convection just south of the Gulf Coast in Louisiana which cuts off a lot of the energy moving into the southern parts of the CWA. This in turn may limit the stability of our atmosphere and just leave us with showers with this system. Although, thunder should not be ruled out quite yet. As the shortwave becomes elongated and dissipates into Thursday, rain chances begin to wane. Going into Friday, another shortwave begins to affect the CWA. Overall, the latter half of this week will have a couple rounds of rainfall. This should help at least a little bit with the drought status and ongoing dry conditions. Temperatures in this period will be warm and highs will be near 80 through the weekend. With anomalous low level warmth, temps may even creep into the mid 80s if conditions prove ideal. The humidity will also be high too with PWs peaking near 1.5" on Thursday and remaining above an inch through the weekend. /10/ && .AVIATION... 00Z TAF discussion: VFR conditions will prevail through the TAF period. A dry cold front will stall over the area through Tuesday, resulting in somewhat breezier northerly winds over the northwestern half of the area, especially at GLH. /DL/ && .PRELIMINARY POINT TEMPS/POPS... Jackson 46 74 54 72 / 0 0 20 63 Meridian 44 74 51 72 / 0 0 3 39 Vicksburg 45 70 53 72 / 0 0 33 68 Hattiesburg 47 76 54 75 / 0 0 4 26 Natchez 47 72 56 73 / 0 0 26 58 Greenville 44 63 50 69 / 0 0 44 67 Greenwood 43 66 50 69 / 0 0 36 61 && .JAN WATCHES/WARNINGS/ADVISORIES... MS...None. LA...None. AR...None. && $$
Area Forecast Discussion...Updated
National Weather Service Saint Louis MO
1023 PM CDT Mon Oct 30 2017 .UPDATE... Issued at 1022 PM CDT Mon Oct 30 2017 Models having hard time dealing with sc deck over northern portions of forecast area as well as mid cloud deck across the south. Adjusted sky cover for the overnight hours as well as temps. Min temps to be a bit warmer than previously forecast due to the increased cloud cover. Byrd && .SHORT TERM... (Through Late Tuesday Afternoon) Issued at 322 PM CDT Mon Oct 30 2017 Frontogenetical band that produced light rain over the area continues to weaken and move southeast this afternoon. Lower atmosphere is drying out, so any remaining precipitation is likely just sprinkles. The RAP continues to show the demise of this band through the afternoon and early evening, so will keep with the dry forecast. Latest GOES-16 imagery is also showing that the mid and high clouds are slowly thinning with the loss of mid level forcing, so will go with a clearing trend tonight. While west-northwest winds will stay up tonight, the clearing skies will set up another cold night with lows falling into the mid-upper 20s except in the St. Louis metro area. A surface high will move across the area tomorrow bringing mainly light winds. After a mainly sunny start, mid-high clouds will stream by afternoon ahead of southern stream system. With the cold start and the clouds moving back in, tomorrow`s highs should be cooler than today`s. Britt .LONG TERM... (Tuesday Night through Next Monday) Issued at 322 PM CDT Mon Oct 30 2017 A short wave and accompanying low level WAA will bring a threat of rain to mainly parts of southeast MO and southern IL Tuesday night into Wednesday. A brief rain/snow mix is not entirely out of the question on the northern fringe of the precipitation shield as evaporative cooling comes into play. A pair of low pressure systems will form in the plains Wednesday night. A cold front with the southern low will track south ahead of the attendant cold front to north central Oklahoma, while the northern low and cold front will approach central Missouri by early Thursday morning. The cold front will push into southeast Missouri and southwestern Illinois and stall with scattered showers possible due to upper level disturbances overriding the boundary through Thursday. The boundary will then begin to lift northward as a warm front on Friday. There are timing and placement issues between the ECMWF and GFS with regards to just how far north the warm front moves north of Interstate 70. Afterwards both the GFS and ECMWF display timing differences on how fast the front pushes through the region on Monday with showers and thunderstorms Sunday Night-Monday. Temperatures will begin continue to trend to above normal seasonal values this weekend into early next week. Kelly && .AVIATION... (For the 00z TAFs through 00z Tuesday Evening) Issued at 639 PM CDT Mon Oct 30 2017 Surface ridge to slowly build in. In the meantime, VFR skies to clear out and west to northwest winds to diminish. Winds to back to the west to southwest by midday on Tuesday. SPECIFICS FOR KSTL: Surface ridge to slowly build in. In the meantime, VFR skies to clear out and northwest winds to diminish. Winds to back to the west by midday on Tuesday. Byrd && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && $$ WFO LSX
Area Forecast Discussion
National Weather Service Marquette MI
735 PM EDT Mon Oct 30 2017 .SHORT TERM...(This evening through Tuesday) Issued at 356 PM EDT MON OCT 30 2017 ...Lake effect snow increases this evening... Upper low has settled over Lk Superior. 995mb sfc low is over eastern Lk Superior while much stronger 970mb low is lifting north over Quebec. Weaker shortwaves sliding on southern edge of upper low has supported light rain/snow showers over much of Upper Michigan today. Based on recent runs of HRRR and other guidance, expect low on eastern Lk Superior to slide east toward stronger low by early this evening. This shifting of the low will allow a strong sfc trough currently over northern Lk Superior to sweep south across Keweenaw as early as 23z/7 pm ET and then into west and ncntrl Upper Michigan 01z-04z/9pm-12am ET. Expect a brief period of heavy lake enhanced snow as the trough moves through. Vsby could be down to less than 1/4sm as this occurs. Snow amounts may push 1-2 inches in brief time. Due to lingering warm air near sfc, greatest snow accum will occur over higher terrain but even some slushy accums will also occur at lower elevations. Once the trough moves through, north winds could gust over 20 mph but don`t think the blowing snow will be big issue as sfc temps are still kind of marginal. North flow lake enhanced snow will increase overnight for favored west and north central higher terrain. Not a lot of large scale lift through the night for enhancement, but deep moisture to 10kft and sufficient over water instability with h85 temps down to -7c to -10c (Lk Superior water temps around 7-8c) will favor moderate to heavy lake enhanced snow overnight, especially west U.P. Continued the winter weather advy for lake effect snow for much of the west and north central. Also added Alger into the advy as western portions could get into some heavier snow overnight tonight. Total snow amounts by late Tue morning most areas in the advy should at least be 3-5 inches but isolated amounts could be higher over far west higher terrain. Away from the lake effect areas could be some light snow showers late evening/early overnight, but limited large scale forcing should quickly focus the better snow shower chances closer to lake effect areas near Lk Superior. On Tue, lingering higher chances for lake effect for NW flow areas of west and ncntrl, but even that should end mid to late aftn as winds back W to SW on northern edge of high pressure diving into the cntrl Plains. Mostly cloudy and chilly day for most on Tue with low to mid 30s and possibly a 40F degree reading at MNM. .LONG TERM...(Tuesday night through Monday) Issued at 333 PM EDT MON OCT 30 2017 Nam shows a trough over the upper Mississippi river valley 00z Wed which remains over the upper Great Lakes through 00z Fri. Nam shows some deeper moisture and 850-500 mb q-vector convergence moving through the area wed afternoon through Thu. Best chances for pcpn look to be wed afternoon and wed night. In the extended, GFS and ECMWF show a 500 mb trough and closed low in the Pacific NW 12z Fri with zonal flow across the upper Great Lakes. This trough digs into the western U.S. 12z Sat with zonal flow staying over the area. Broad troughing moves into the Rockies 12z Sun which remains into 12z Mon. A shortwave does move into the Canadian prairies 12z Mon with some colder air that moves into the area later Monday. Temperatures look to stay near normal this forecast period and it is cold enough for some lake effect pcpn. && .AVIATION...(For the 00Z TAFS through 00Z Tuesday evening) Issued at 727 PM EDT MON OCT 30 2017 Westerly winds will favor mainly VFR conditions at KSAW into early this evneing, even though there could be some MVFR conditions occasionally as rain/snow showers begin to develop. A sfc trough sagging southward across Lake Superior will bring a brief period of heavier snow, with conditions down to LIFR, along with winds shifting to the north and becoming gusty, initially at KIWD and KCMX and then shifting eastward into KSAW by late evening. Behind the trough into Tuesday morning, expect lake effect snow showers to continue with general IFR vsby and MVFR cigs. The worst conditions still look to be at IWD and CMX as winds becoming more NW is not as favorable for lower conditions at SAW due to the downsloping nature of the wind. There will be a brief window late in the evening that a more northerly wind may drop ceilings and visibilities, right along the trough, but condtions should then steadily improve at KSAW. && .MARINE...(For the 4 PM Lake Superior forecast issuance) Issued at 356 PM EDT MON OCT 30 2017 Winds will veer from WNW to N and increase to 20 to 30 knots this evening as a cold front/trough drops south across the lake. Winds will remain between 20 to 30 knots through much of the week. && .MQT WATCHES/WARNINGS/ADVISORIES... Upper Michigan... Winter Weather Advisory until 2 PM EDT Tuesday for MIZ006. Winter Weather Advisory until 8 AM EDT Tuesday for MIZ004-005. Winter Weather Advisory until 8 AM EDT /7 AM CDT/ Tuesday for MIZ002-003-009-084. Lake Superior... None. Lake Michigan... None. && $$ SHORT TERM...JLA LONG TERM...07 AVIATION...KEC MARINE...JLA
Area Forecast Discussion
National Weather Service Pueblo CO
256 PM MDT Mon Oct 30 2017 .SHORT TERM...(This evening through Tuesday) Issued at 256 PM MDT Mon Oct 30 2017 This afternoon low stratus continues to cover the southeast plains and evening up into the upper Arkansas River valley. Satellite shows increasing high level clouds acrs western portions of the forecast area. There`s not much in the way of pcpn this afternoon over the lower elevations east of the mtns, although some locations in and near the mtns are likely seeing some light pcpn. Late tonight and thru early afternoon Tue, an upper level weather system will move east-southeast acrs the state. Also tonight, favorable jet dynamics is expected to play a role. This evening pcpn is expected to begin increasing acrs southern CO. The models continue to show banded pcpn and the latest GFS and NAM are in fairly good agreement with the location of a band stretching from western Saguache and northern Mineral counties, eastward acrs the nrn Sangres and then eastward acrs southern Pueblo county, Otero and Bent counties. On the other hand, the HRRR does not show this band. In the late night hours and early Tue morning, the models show high probability of snow along the Continental Divide and along the Sangres (mainly northern portions of the Sangres). There may also end up being a band of pcpn in the late night hours over southern El Paso and northern Pueblo counties, and over Crowley and Kiowa counties. At this time, models show little in the way of snow accumulation at the lower elevations, but the higher elevations are still expected to get several inches, and the current Winter Wx Advisory still looks warranted, and will not make changes. Tue, pcpn is forecast to decrease/end over the eastern areas thru the morning hours, while snow continues along the Continental Divide. As the upper disturbance moves out of the area in the afternoon, pcpn will also mostly end over western areas. In the afternoon there could just be some isolated lingering light pcpn over the higher peaks. Temps acrs the southeast plains should be much warmer than today, with highs in the upper 40s to lower 50s over El Paso county, and in the 50s over the rest of the southeast plains. The high valley locations should have high mostly in the 50s. .LONG TERM...(Tuesday night through Monday) Issued at 256 PM MDT Mon Oct 30 2017 Tuesday night through Thursday...Save for a few lingering snow showers along the Continental Divide Tues eve, look for dry conditions and gradual warming as the upper trough moves out. Brisk northwest flow Wed will transition to a more relaxed westerly flow for Thu. Expect max temps in the 50s to around 60F for the high valleys, and mid 60s to mid 70s for the plains. Friday through Monday...Long range models continue to show the upper flow strengthening and becoming more southwesterly over the weekend, as a strong upper low pressure system rotates over the Pacific NW. Expect isolated snow along the Continental Divide and especially the central mts over the weekend. Temps will warm into the upper 50s to around 60F for the high valleys, and mid 60s to mid 70s for the eastern plains. Sunday night a shortwave is forecast to cross the northern Rockies, pushing a cold front down into Colorado overnight. This will cool temps across the forecast area by 5 to 10 degrees for Monday, with highs in the 50s for the high valleys, and upper 50s to mid 60s for the plains. Moore && .AVIATION...(For the 00Z TAFS through 00Z Tuesday evening) Issued at 256 PM MDT Mon Oct 30 2017 KCOS will probably have MVFR MVFR ceilings/vsby tonight through midmorning Tue. However, there will be chances of snow through this period, and conditions could be IFR at times. VFR conditions should return for Tue afternoon. KPUB should have low VFR ceilings into the evening, but ceilings are expected to lower into the MVFR category later this evening and there will then be chances for snow into Tue morning. Snow could at times reduce ceilings/vsby into the IFR category. VFR conditions should return for late Tue morning and thru the afternoon. KALS is expected to have VFR conditions thru at least this evening. However, this evening pcpn chances are expected to increase, with chances for pcpn into Tue morning. Ceilings will lower tonight and if snow falls tonight/Tue morning, ceilings/vsby could lower into the MVFR category or even into the IFR category at times. && .PUB WATCHES/WARNINGS/ADVISORIES... Winter Weather Advisory from 9 PM this evening to 6 PM MDT Tuesday for COZ060-066-068-073-075-080-082. && $$ SHORT TERM...28 LONG TERM...MOORE AVIATION...28