Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 11/08/18

Area Forecast Discussion
National Weather Service Albany NY
923 PM EST Wed Nov 7 2018 .SYNOPSIS... Seasonable temperatures are expected tonight into tomorrow with mainly dry conditions. A storm system will bring some rain and mountain show to the the region for Friday into Friday night. Cool and breezy conditions are expected over the weekend, with some lake- effect snow showers for western and northern areas. && .NEAR TERM /UNTIL 6 AM THURSDAY MORNING/... As of 920 PM EST...A broad upper level trough extends from the northern Plains eastward across the Midwest and Great Lakes. Although the low level flow is out northwest, there is generally west to southwest flow aloft. Some cold air advection has been occurring throughout and with the colder air passing over Lake Ontario, some light lake-effect showers have been impacting parts of the western Adirondacks. With boundary layer temps warm enough, this precip has been falling as rain showers. However, surface temps will be falling and this on and off light precip may changeover to snow showers for the overnight. Both the 3km NAM Nest and HRRR suggest the flow will remain fairly steady state, so basically areas north of Old Forge and Indian Lake may see some light snow showers through the overnight. Any accumulation looks fairly light, generally under an inch. Outside of the lake-effect activity, it will remain partly to mostly clear and seasonably chilly for tonight. Some cirrus clouds moving up from the mid-Atlantic are expected for southern areas, but it should stay dry. A decreasing pressure gradient and nocturnal effects should help reduce winds for tonight after some gusts this evening of up to 24 kts with the passage of a weak trough of low pressure. Lows will generally be in the 30s. && .SHORT TERM /6 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/... Some additional lake-effect rain or snow showers will continue across the western Adirondacks for Thursday (mainly early in the day). Otherwise, the weather will remain fairly similar, with a broad trough located just west of the region keeping it fairly dry with a partly cloudy sky. Temps will be cooler on Thursday compared to Wednesday thanks to chillier temps aloft, with highs only reaching into the 40s. High pressure will move across the region for Thursday night, allowing any lake-effect precip to end and skies to be partly to mostly clear. Lows will be in the upper 20s to mid 30s. The next storm system will be arriving for Friday. As a shortwave dives out of Canada into the trough, it will sharpen and cut off over the Great Lakes. Meanwhile, a surface storm over the Ohio Valley will be lifting towards the eastern Great Lakes, while a secondary low develops off the mid-Atlantic states. This system will tap into some Gulf moisture. While it may be dry early in the day Friday, precip will expand across the region for later Friday morning and through the rest of the day. Valley areas will mainly see rain (cannot rule out a few snowflakes to start, but no accumulation). Meanwhile, high terrain areas (above 1500 feet) will see rain and snow, but any snow accumulation looks limited to areas above 2500 ft, as the southerly flow at the surface allows some warmer air to move northward within the boundary layer. The highest terrain of the Adirondacks and southern Greens may see a few inches of snow accumulation from this storm. As the storm along the coast deepens, frontogenesis along the coast could allow for some heavier precip, so cannot rule out some moderate to locally heavy rain, especially for southeastern areas. Precip looks to be tapering off on Friday night after midnight, as the secondary low lifts towards coastal Maine. Nearly steady temps in the mid 30s to mid 40s are expected for Friday into Friday night. && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... The long term forecast period starts out active and ends active with some drier weather during the middle of the long term period. On Saturday expect some measurable lake effect snow downwind of Lake Ontario across the western Adirondacks with some scattered rain or snow showers across the Mohawk Valley, Lake George Saratoga region, southern Vermont, and the northern Berkshires. H8 temps are -4 C to -8 C with Lake Ontario temp still around 10 C, so plenty of differential to work. A this time expect generally 1 to 4 inches of snow across the western Adirondacks with the greatest accumulation along and north of Route 28. Highs on Saturday are expected to be in the upper 20s to mid 40s. On Saturday night the lake effect band shifts south into the southern portions of the western Adirondacks as well as the Mohawk Valley and Schoharie Valley. Accumulations look to be light at this time, but up to another inch of snow accumulation is possible. Lows will be in the upper teens to upper 20s. Sunday through Monday...Looks to be mainly dry as a large ridge of high pressure builds across the eastern seaboard. It will continue to be chilly with highs on Sunday in the upper 20s to lower 40s with lows Sunday night in the mid teens to upper 20s, and highs on Monday in the upper 20s to mid 40s. More active weather is expected Monday night into Wednesday as low pressure moves east from the upper Great Lakes as a secondary area of low pressure is expected to form along the middle Atlantic coast on Tuesday morning. A secondary trough of low pressure is then expected across the region on Wednesday bringing more cold air to the region. Lows Monday night are expected to be in the mid 20s to mid 30s with highs on Tuesday in the mid 30s to mid 40s. Lows Tuesday night are expected to be in the upper teens to lower 30s with highs on Wednesday in the mid 20s to around 40. && .AVIATION /03Z THURSDAY THROUGH MONDAY/... VFR conditions are expected to prevail over the next 24 hours ending 00Z Friday. Some intervals of low and high clouds are expected through the period along with steady west to southwest winds. The periods of low and high clouds and steady winds should prevent any widespread fog through tonight and early Thursday morning. Winds diminish to less than 10 kts from the southwest tonight then increase to around 10 kts from the southwest to west Thursday morning. The exception will be at KALB, KGFL and KPSF where winds will be west to northwest with gusts up to 24 kts this evening. Outlook... Thursday Night: No Operational Impact. NO SIG WX. Friday: High Operational Impact. Definite RA. Friday Night: High Operational Impact. Definite RA. Saturday: Low Operational Impact. Breezy Slight Chance of SHRA. Saturday Night: No Operational Impact. NO SIG WX. Veterans Day: No Operational Impact. NO SIG WX. Sunday Night: No Operational Impact. NO SIG WX. Monday: Low Operational Impact. Slight Chance of SHRA. && .FIRE WEATHER... Mainly dry conditions are expected tonight into tomorrow. RH values will be as low as 50 percent on Thursday with northwest winds of 5 to 10 mph. A wetting rainfall is expected across the entire area on Friday into Friday night. && .HYDROLOGY... Outside of a few lake effect rain and snow showers over the western Adirondacks, dry weather is expected across the area for tonight through early Friday morning. Rivers and streams have been rather elevated due to recent rainfall (especially across western New England) and this period of dry conditions will allow for water levels to slowly recede. More rain (and some mountain snow) is expected to return for Friday morning through Friday night. Total QPF is currently forecasted to be 0.75 to 1.25 inches across the region, which should allow for more rises on rivers and streams. Current river forecast and MMEFS solutions show some rivers may reach action stage (especially the Hoosic and Housatonic Rivers), but no flooding is currently forecasted. If QPF were to increase, then some minor flooding would be possible, so continue to check for any changes in the forecast over the next few days. Behind this system, colder and drier conditions (outside of some lake effect snow showers for northwestern areas) are expected over the weekend. River and stream levels levels should slowly recede. For details on specific area rivers and lakes, including observed and forecast river stages and lake elevations, please visit the Advanced Hydrologic Prediction Service /AHPS/ graphs on our website. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. MA...None. VT...None. && $$ SYNOPSIS...Frugis NEAR TERM...Frugis/11 SHORT TERM...Frugis LONG TERM...11 AVIATION...11/NAS FIRE WEATHER...Frugis HYDROLOGY...Frugis
Area Forecast Discussion
National Weather Service La Crosse WI
546 PM CST Wed Nov 7 2018 .SHORT TERM...(This evening through Thursday) Issued at 237 PM CST Wed Nov 7 2018 Flurries and even some freezing drizzle in the higher elevations were seen along and east of the Mississippi River Wednesday afternoon as a shortwave trough continued to rotate through the northwest flow aloft. At the surface, a fairly tight pressure gradient brought gusty northwesterly winds to the area, though these should subside a bit as high pressure continues to build in overnight. The high pressure should also be enough to break up the persistent cloud cover at least a little bit, but the RAP has trended toward keeping the clouds around all night, which could lead to temperatures being a few degrees higher than forecast. Thursday will then be quiet as high pressure continues to build in, but clouds will be on the increase through the afternoon. Temperatures will remain cool, with highs in the 30s. .LONG TERM...(Thursday night through Wednesday) Issued at 237 PM CST Wed Nov 7 2018 Attention then turns to snow chances Thursday night through Friday. Good model agreement of shortwave energy ejecting eastward out of the Central Plains Thursday evening. In addition, should be some decent mid-level frontogenesis in the area, but not great agreement as to where it initially sets up. 07.12Z NAM/ECMWF/Canadian develop the band to the northwest and slide it through the entire area. In contrast, the 07.12Z GFS develops it directly over the forecast area, keeping northwest portions of the area dry. Bottom line, should be a band of light snow (an inch or less) that moves through at least part of the forecast area through Friday morning. Meanwhile, a broader upper level trough will drop southeastward out of North Dakota and spin up a surface low. This will bring more cold air to the region (highs in the upper 20s to mid 30s). Also, more snow is expected with this system through Friday afternoon, mainly along and west of the Mississippi River. Once again, model differences in placement don`t allow for much confidence in the forecast, but northeast Iowa looks to have the best shot for more snow. In addition, there is good model agreement of a fairly tight pressure gradient over the area, so should some pockets of heavier snow develop, strong winds could lead to some temporary travel issues. All snow should come to an end by Friday evening, with totals from Thursday night through Friday being generally in the 1 to 2 inch range. Zonal upper level flow will then set up for the weekend, with more bits of shortwave energy sliding through Saturday night and possibly bringing some light snow or flurries. Sunday will see a slight "warmup" with highs into the 30s area-wide. A return to upper level troughing is then on tap for the beginning of the work week, with more cold air spilling in from the north. There are also hints of more light snow with this, though surface high pressure will quickly build in Monday night into Tuesday, keeping the area dry through the remainder of the period. && .AVIATION...(For the 00Z TAFS through 00Z Thursday evening) Issued at 545 PM CST Wed Nov 7 2018 The 00Z TAF set will have significant delay to the MVFR conditions overnight from the previous forecast. Took a more pessimistic approach based on satellite expanse of the OVC MVFR CIGS over all of MN/IA and slowly shifting east. Also, PIREPS indicating the cloud depth is about 1500ft over the area, thinning to around 1kft on western cloud edge. 1500 ft would indicate a tougher mix out of the clouds via subsidence. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...None. MN...None. IA...None. && $$ SHORT TERM...CA LONG TERM...CA AVIATION...Baumgardt
Area Forecast Discussion
National Weather Service Burlington VT
955 PM EST Wed Nov 7 2018 .SYNOPSIS... A slow cooling trend continues across the North Country with scattered mainly mountain rain and snow showers. Temperatures tonight drop into the mid 30s to lower 40s with highs on Thursday warming into the upper 30s to upper 40s. Low pressure will track toward our region on Friday into Saturday, with a mix of rain and snow. Some snow and ice accumulation is likely in the mountains, with limited accumulation anticipated in the warmer valley locations. Temperatures will cool into the 30s to lower 40s with overnight lows holding in the upper 20s to mid 30s. && .NEAR TERM /THROUGH THURSDAY NIGHT/... As of 955 PM EST Wednesday...Starting to see flow aloft becoming more westerly tonight and this is helping to decrease the areal coverage of lake effect precipitation with just some isolated showers moving across the area. Going forecast has this decreasing trend handled well and only tweaks needed were to match temperature and dew point trends. Previous Discussion... Mid/upper level trof continues to deepen across the ne conus with fast westerly flow aloft as VAD 500mb winds show values of 90 to 110 knots. Water vapor and RAP show weak embedded 5h vort entering the slv and better 850 to 500mb moisture slowly advecting south to produce isolated to scattered shower activity. This general idea of chc pops mainly across the mountains looks reasonable based on moisture/lift thru 06z. In addition, aligned 925mb to 850mb west/southwest flow of 35 to 45 knots will help to advect better lake moisture into the dacks, along with enhanced upslope flow to produce likely pops for this evening. As better dynamics shifts east and winds slowly become west/northwest expect moisture to decrease in areal coverage, along with precip chcs. A light dusting of snow is possible above 2000 feet over the dacks and northern Green Mountains. Temps will range from the mid 20s summits to lower 40s warmer valleys. Still expecting some gusty winds this aftn with kmss gusting to 37 knots, these winds will decrease aft sunset as low levels stabilize and pres gradient slowly weakens. For Thursday into Thursday...weak sfc high pres and mid/upper level ridge builds across our cwa. Deeper rh profiles show good drying aloft, however with bl moisture, 5h energy and moisture trapped below 850mb, expect mostly cloudy skies in the mountains and partly sunny valleys. A few isolated rain/snow showers are possible, but areal coverage based on moisture profiles will be minimal. Temps range from the upper 20s/lower 30s summits to mid/upper 40s valleys on Thursday. Thursday night will be quiet and chilly as 1030mb high pres builds into our fa. The uncertainty will be amount of clearing, as winds will become light and trrn driven. Clouds will have a significant influence on sfc temps with initial thoughts lows ranging from mid 20s to mid 30s most locations. && .SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/... As of 345 PM EST Wednesday...Overall little change from what we`ve been highlighting for the end of the work week and into the first half of the weekend. Expect we`ll see a widespread precipitation event Friday through Saturday with varying precipitation types in the higher elevations and rain in the valley floors. On the broad scale, a full latitude CONUS trough will by digging through the Great Plains and becomes closed off over the Great Lakes on by Saturday. As that upper level low is deepening a surface low develops over the Ohio Valley and pushes up through the Saint Lawrence Valley during the day on Friday. At the same time another surface low develops along the Atlantic coast to create the double barrel low structure that guidance has been keying on for a couple of days now. This setup will bring widespread warm air advection precip to the region which will mostly fall in the form of rain. Because the upper level dynamics are stronger with the northern stream low I would expect that one to intensify more than is currently forecast and for the coastal low to be weaker. That points to a slightly more warm solution with slightly less snow. Guidance still points to a warm nose pushing into the region briefly Friday afternoon which should be enough to cause some mixed precip issues. However the differing ptypes will be above 2000 feet so largely the effects will be minimal where most people live. Still a tad early for exact details but the best chance for snow should be over the Adirondacks with the highest potential for ice accumulation in the high peaks of the Adirondacks and the Greens. By Saturday morning, the precipitation becomes more showery and we`ll start to see some mountain showers along with a lake effect response. Precip tapers off Saturday night as the low(s) pull farther northeast of the region and high pressure begins to build in from the west/southwest. && .LONG TERM /SUNDAY THROUGH WEDNESDAY/... As of 401 PM EST Wednesday...Cold temps and quiet weather return Sunday into Monday as high pressure builds in. Expect temps to stay on the chilly side Sunday as we`ll be mostly overcast skies under cold air advection. This pattern is typical where the temp at like 9am or 10am in the morning holds steady through out the day. So I dropped temps by a couple degrees and that puts our highs in the upper 20s to low 30s. By mid week another strong low pressure system looks to lift north bringing another round of precip. The difference this time is that temps will start off much colder and so we`ll see a period of snow before the warm air finally overrides and transitions the North Country back to steady rain. && .AVIATION /03Z THURSDAY THROUGH MONDAY/... Through 00Z Friday...Overall looking at VFR conditions through the period. Some lake effect rain showers from Lake Ontario may reach KSLK and cause some MVFR conditions through 06z before precipitation moves south of the area. Gusty west to southwest winds will continue with gusts in the 15 to 25 knot range through about 12z before the gusts taper off and winds remain from the west around 10 to 15 knots. Outlook... Thursday Night: VFR. NO SIG WX. Friday: Mainly VFR, with local MVFR possible. Definite RA. Friday Night: Mainly MVFR, with local IFR possible. Definite RA. Saturday: Mainly VFR, with local MVFR possible. Chance SHRA, Chance SHSN. Saturday Night: Mainly VFR, with local MVFR possible. Chance SHSN. Veterans Day: VFR. NO SIG WX. Sunday Night: VFR. NO SIG WX. Monday: VFR. Slight chance SHSN. && .MARINE... Lake wind advisory remains in effect tonight for southwest winds of 15 to 25 knots and gusts to 30 knots. Expect localized wave heights near 4 feet in the open waters and this will create rather choppy conditions. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...None. NY...None. && $$ SYNOPSIS...Taber NEAR TERM...Evenson/Taber SHORT TERM...Deal LONG TERM...Deal AVIATION...Evenson/Taber MARINE...Clay
Area Forecast Discussion
National Weather Service Lincoln IL
902 PM CST Wed Nov 7 2018 .UPDATE... Issued at 852 PM CST Wed Nov 7 2018 Cloud deck hugging the I-74 corridor continues to inch southeast early this evening and was not handled well by the operational models. High resolution forecast soundings from the 3km NAM suggest moisture in the 1200-2000 foot layer to be trapped under a developing subsidence inversion overnight into Thursday morning. Although the latest HRRR holds on to the clouds the longest over the northern half of our forecast area, it appears the clouds start to scatter out before dawn Thursday which looks to be too quick based on the soundings. Will expand the cloud deck further south for tonight to at least the I-72 corridor well after Midnight. Based on the increase in cloud cover tonight, will edge temperatures back up for overnight lows with morning lows in the upper 20s to lower 30s. The low clouds may scatter out late tomorrow morning as a developing easterly flow draws in somewhat drier air in the low levels with a weakening of the inversion noted on forecast soundings. However, any decrease in the lower cloud cover will be offset by increasing high level clouds as the day wears on ahead of our next weather system. It still appears any rain and snow in our area will hold off until tomorrow evening. Updated forecast should be out by 915 pm. && .SHORT TERM...(This evening through Thursday) ISSUED AT 206 PM CST Wed Nov 7 2018 Quiet weather expected in the short term, as high pressure continues to build southeast. With abundant dry air aloft, Thursday looks to remain precip-free as the storm system starts to approach from the southwest. Not looking for a lot of change in temperatures for Thursday, though the far southeast CWA should be about 5 degrees cooler than today. .LONG TERM...(Thursday night through Wednesday) ISSUED AT 206 PM CST Wed Nov 7 2018 Overall pattern still remains unseasonably cold across the Midwest into the middle of next week. Several deep upper troughs will swing through the region, accompanied by shots of Arctic air (850 mb temperatures as low as -15C at times). The coldest day looks to be Saturday, when highs may struggle to reach freezing over the northern CWA, after an early morning featuring wind chills in the single digits. Shortwave currently over southern Idaho will help sharpen as it swings into the Plains on Thursday. Latest model guidance continues to show widespread precipitation over the forecast area by mid evening, with model soundings suggesting a quick change from rain to snow. Amounts around an inch or so still appear reasonable over areas north of I-72 Thursday night, with the snow shifting northeast early Friday morning. Clipper system behind it will bring a quick shot of rain/snow across the north Friday afternoon and evening, but no accumulations are expected with this feature. With the system early next week, the longer range models are in good agreement with the upper level features, though the GFS is a bit faster with the progression of the upper trough. The precipitation shield is a much different story, though, as the European (especially) and Canadian models have much more of a deformation zone present. The GFS largely bypasses any precip for our area. Will mainly focus PoP`s on the Monday night time frame, where another light dusting is possible. && .AVIATION...(For the 00Z TAFS through 00Z Thursday evening) Issued at 506 PM CST Wed Nov 7 2018 Significant changes already made to PIA and BMI bringing in MVFR cigs over the next hour with the main question how far south the lower cigs will get and how long they will be in our area tonight/Thu morning. Recent runs of the HRRR model continues to point towards a more pessimistic forecast for the overnight and early morning hours with MVFR cigs spreading into our southern TAF areas after Midnight before we see the clouds start to slowly decrease during the mid-morning hours with VFR conditions expected during the afternoon. Even that is in doubt as the latest 3km soundings suggest moisture trapped below a subsidence inversion around 2000 feet AGL late tonight through Thu morning may hold the MVFR cigs longer than what is currently forecast. Light northwest to north winds expected tonight should start to veer more into a northeast then east direction on Thursday with speeds of 10 kts or less. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...Smith SHORT TERM...Geelhart LONG TERM...Geelhart AVIATION...Smith
Area Forecast Discussion...UPDATED
National Weather Service North Platte NE
753 PM CST Wed Nov 7 2018 .UPDATE... Issued at 753 PM CST Wed Nov 7 2018 The RAP and HRRR models have ingested the 00z upper air data. A blend of these models plus the HREF are in place for a new snowfall forecast. The forecast suggests slightly less snow across swrn Nebraska but slightly more across nrn Nebraska. 2 or 3 areas of snow are expected to affect parts of western and north central Nebraska tonight and Thursday. The area of snow underway across sern MT per radar may affect highway 20 across northern Nebraska late tonight and Thursday. The area of snow currently underway across sern WY may affect I-80 and the Sandhills later this evening, overnight and Thursday. The area of snow underway across swrn Nebraska should exit that area by 6 am Thursday morning. && .SHORT TERM...(This evening through Thursday) Issued at 302 PM CST Wed Nov 7 2018 As a winter system crosses the area tonight, isentropic upglide will be rather substantial across southwest and central Nebraska overnight. Some potential for heavier banded convective snow, given areas of negative EPV and even some weak elevated CAPE. The upper jet axis is oriented from east central Co across the Nebr/KS border. This places southwest and central Nebraska in the left entrance region of the jet, which is less favorable for divergence aloft. However, forecast model soundings do indicate favorable saturation in the DGZ, so dendrite formation and growth should be favorable. Snowfall overnight is expected to reach 1 to 3 inches in the winter weather advisory area, with additional snowfall Thursday. For Thursday, total snowfall amounts are similar to previous forecast, with amounts from 4 to 6 inches south of a Grant through North Platte and Brady. Within winter weather advisory area, areas north of this line can expect 2 to 4 inches. Even into the Sandhills of north central Nebraska such as Gordon, Valentine and Ainsworth can expect up to an inch. Isentropic downglide kicks in across the area by 15Z, with an en to the snow from west to east during the day. Winds will remain light southeast around 5 mph where snow continues Thursday, while becoming north across the western Sandhills, where the snow ends. A cold day, with highs from around 30 most areas. .LONG TERM...(Thursday night through Wednesday) Issued at 302 PM CST Wed Nov 7 2018 Much colder air drawn in Thursday night with some clearing skies. Lows mostly reach the mid teens. Northwest winds increasing overnight, becoming 15 to 20 mph across the north central, where wind chills will fall to the low single digits most areas. These low wind chills, even near 5 below Valentine and Gordon areas will Occur Friday morning. Breezy conditions through the day east of highway 83. With the winds, there will be patchy blowing snow, especially for counties in and around Custer County. Highs only around 20 parts of north central, to near 30 the Imperial area. Upper level ridging will remain in place across the eastern Pacific as we head into the weekend and first of next week. Northwest flow aloft will prevail downstream across our region east of the ridge. Some moderation in highs Saturday to the upper 30s to mid 40s, ahead of the next trough in the Northern Plains. expected during the weekend, before another shot of cold air Monday with highs upper 20s to lower 30s. A nice warm up by Wednesday into the mid 50s as upper level ridging builds east. The extended period looks mainly dry, with no significant weather disturbances noted. && .AVIATION...(For the 00Z TAFS through 00Z Thursday evening) Issued at 554 PM CST Wed Nov 72018 Across wrn and ncntl Nebraska...areas of MVFR/IFR in -SN and low ceilings will become IFR/local LIFR overnight and improve to MVFR/local IFR from west to east 00z Thursday evening. 2 or 3 areas of snow are expected to affect parts of western and north central Nebraska tonight and Thursday. The area of snow underway across sern MT may affect highway 20 across northern Nebraska late tonight and Thursday. The area of snow currently underway across sern WY may affect I-80 and the Sandhills later this evening, overnight and Thursday. The area of snow underway across swrn Nebraska should exit that area by 12z Thursday morning. && .LBF WATCHES/WARNINGS/ADVISORIES... Winter Weather Advisory until 6 PM CST /5 PM MST/ Thursday for NEZ036>038-056>059-069>071. && $$ UPDATE...CDC SHORT TERM...Roberg LONG TERM...Roberg AVIATION...CDC
Area Forecast Discussion
National Weather Service Marquette MI
701 PM EST Wed Nov 7 2018 .SHORT TERM...(This evening through Thursday) Issued at 307 PM EST WED NOV 7 2018 WV imagery and RAP analysis indicated a broad mid/upper level trough through the central CONUS leaving unseasonably cold air entrenched across the region from the plains through the western Great Lakes. A weak shortwave trough over central Upper Michigan was sliding quickly to the east with no significant shrtwvs upstream that are expected to impact the short term. At the surface, cyclonic northwesterly flow persisted through the northern Great Lakes between a ridge through the plains and low pressure over nrn Quebec. 850 mb temps to around -10C along with lingering deep moisture supported relatively unorganized multiple wind parallel lake effect snow bands into the nrn cwa with only brief periods of lower vsby and only a few inches of accumulation over the higher terrain in the west so far. Tonight, the deeper moisture is expected to move out this evening with inversion heights dropping to around 5k ft resulting in diminishing LES. Additional accumulations of around an inch will still be possible for nw flow favored locations. Although the LES should end farther inland with loss of larger scale lift/moisture, some low clouds will persist with exception over far southern Menonminee county. Thursday, expect some lingering nw flow LES as 850 mb temps remain around -11C, even as sfc ridging builds into the area with diminishing winds. Any additional accumulations should remain at a trace or less an an inch. Under mostly cloudy skies, highs will remain below average with readings in the upper 20s inland west to the mid or upper 30s over the south and east. .LONG TERM...(Thursday night through Wednesday) Issued at 404 PM EST WED NOV 7 2018 Focus is on late Thu night into early Sat morning when significant snowfall is possible. Overall setup is for a sharp upper trough moving into the region Thu night to possibly deepen into a compact low over the CWA Fri before exiting E Fri night. At the surface, a trough will set up from the lower Great Lakes across the U.P. and into Lake Superior. 850mb temps will start out around -11C then cool to closer to -16C once the upper trough/low moves through. Moderate to heavy lake enhanced snow showers are expected in the vicinity of the surface trough at first, then spreading as the upper feature moves in. LES then takes hold Fri night behind the system with N-NW winds, diminishing late Fri night through Sat. Snowfall details depend on the track and strength of the upper forcing and the tracking of the surface trough. The NAM is an outlier in showing a stronger upper feature, and the surface trough more the SW, which then leads to substantially more precip than other models. Staying more toward the consensus leads to a few inches of snow over the S- central U.P. and several inches elsewhere. Of course, if the surface trough hangs over Lake Superior longer, snowfall amounts will be lower. Snow ratios will likely be in the low to mid teens most of Friday, increasing Fri night when the event transitions for pure LES. Winds gusting to 30-40 mph at times may also lead to blowing snow near Lake Superior. With the continued uncertainty, did not issue any headlines at this time, but continue to highlight in the HWO. Beyond that, still seeing active weather with off and on chances for lake effect snow, but nothing significant of any predictability. && .AVIATION...(For the 00Z TAFS through 00Z Thursday evening) Issued at 654 PM EST WED NOV 7 2018 While MVFR conditions are expected much of the time tonight, there could be periods of IFR vsby under lake effect snow bands at KCMX this evening. As snow diminishes to flurries to Thursday, MVFR cigs will persist at all sites through much of the day, except for the possibility of brief improvement to VFR at KSAW. && .MARINE...(For the 4 PM Lake Superior forecast issuance) Issued at 307 PM EST WED NOV 7 2018 No gale events are expected through Thursday. Winds nw at 20-30 kts are expected through Thursday as colder air moves across the Upper Great Lakes. From Friday afternoon into Friday evening, n-nw winds approaching gales could develop with a stronger push of cold air into the region behind a cold front and strengthening low pressures system. && .MQT WATCHES/WARNINGS/ADVISORIES... Upper Michigan... None. Lake Superior... None. Lake Michigan... None. && $$ SHORT TERM...JLB LONG TERM...Titus AVIATION...Voss MARINE...JLB
Area Forecast Discussion
National Weather Service Pueblo CO
259 PM MST Wed Nov 7 2018 .SHORT TERM...(This evening through Thursday) Issued at 237 PM MST Wed Nov 7 2018 An upper level trof will continue to slowly sink south toward CO tonight, and will move over CO thru the day Thu. Western portions of the forecast area are expected to remain dry tonight and Thu. Eastern portions of the forecast area will see a lot of low cloud cover tonight, and the potential for light precip. The HRRR shows very little chance for precip tonight and Thu morning, with mainly just some light precip over El Paso county before midnight. The NAM shows a little more precip, mainly over El Paso county thru the late night hours, and over the far southeast plains. The GFS shows little precip, and mainly has precip from about the I-25 corridor and west in El Paso/Teller county. The low level southeast upslope flow in El Paso county may help get some light precip going, mainly snow, but it is possible that there could be a little freezing drizzle tonight. Precip increases a little in the models on Thu as the upper trof approaches, but mainly over the far southeast plains. Will still go with the potential for maybe around an inch of snow over eastern portions of Kiowa county Thu morning. The GFS has precip Thu afternoon over the Wet mtns and southern I-25 corridor, while the NAM does not. Temps Thu are going to be well below average, with highs mostly in the mid 30s to lower 40s over the southeast plains and the Upper Arkansas River Valley, with lower and mid 40s in the San Luis Valley. .LONG TERM...(Thursday night through Wednesday) Issued at 237 PM MST Wed Nov 7 2018 Operational models and ensemble members are in general agreement into early next week with minor differences. This leads to overall higher forecast confidence with large trough over the Central Plains and ridge developing over the west. This will lead to cooler conditions across the region into early next week. Thursday night through Saturday...expect dry northwest flow through this period with a couple of cold fronts impacting the area, one on Friday and another on Saturday late in the day. As for Friday, the frontal boundary will likely stall out across the far Northeast Plains with cooler temperatures east of an Eads to Lamar line. West of this area, highs on Friday will likely reach into the upper 40s to lower 50s. East of the boundary highs will likely only reach into the upper 30s to lower 40s. By Saturday, flow aloft will transition westerly head of a digging upper level trough out of the Northern Rockies. This will allow much of southern Colorado to warm nicely Saturday afternoon with upper 50s and perhaps a few low 60s across the Eastern Plains. The next frontal boundary will push back west across the Plains during the late afternoon hours into the evening. Much colder air will work in behind the front with temperatures falling into the lower to mid 20s by Sunday morning. Models slightly different on precipitation timing as well. The GFS is most aggressive with developing snowfall along the Palmer Divide by Sunday morning. Sunday through Monday...the next upper disturbance will drop south across the region Sunday into Monday. As mentioned, the GFS is slightly faster with snowfall onset with light snow into the Palmer Divide region by Sunday morning. The ECMWF is slightly slower and brings snow into the region by mid day. Expect at least light rain and snow to develop over the mountain areas by Sunday morning and expand eastward across the Plains Sunday night into Monday. At this time, temperatures look like they could be cold enough for snowfall, especially during the overnight hours across the region. Afternoon highs on Sunday and Monday only look to reach the mid to upper 30s, so during the daylight hours, there could be rain and snow mixing across the lower elevations. As for snow totals, its currently too early to tell. Both the GFS and ECMWF have the heaviest snowfall banked along the Eastern Mountains and Raton Mesa area where northeast upslope flow in the lower levels is preferred. This will have to be monitored for consistency in model runs. The main model differences are in timing, with the GFS quicker to bring the system south into the Southern Plains, while the ECMWF brings in a secondary surge Monday night with another round of light snow clearing north to south by Tuesday morning. Tuesday and Wednesday...high pressure over the western states is forecast to build east across the Rockies with drier and warmer conditions expected across the area. Afternoon highs will warm back into the 40s on Tuesday and 50s on Wednesday. Mozley && .AVIATION...(For the 00Z TAFS through 00Z Thursday evening) Issued at 237 PM MST Wed Nov 7 2018 KALS is expected to see VFR conditions thru the forecast period. KPUB will the ceiling lower this evening, with MVFR conditions expected to develop and continue into about midmorning Thu. There could be a few light snow showers tonight. KCOS will see the ceiling lower this evening, with MVFR and maybe even occasional IFR conditions until early Thu morning. Some light snow will probably develop this evening and be possible thru the night, there could be some light freezing drizzle at times. North winds are expected to develop near 12Z on Thu and then the low clouds should dissipate. && .PUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...28 LONG TERM...MOZLEY AVIATION...28
Area Forecast Discussion
National Weather Service Tucson AZ
836 PM MST Wed Nov 7 2018 .SYNOPSIS...Dry conditions will continue into early next week. Daytime temperatures will be several degrees above average today then gradually cool into the upcoming weekend. A trough of low pressure will bring additional cooling early in the new week. && .DISCUSSION...Clear skies this evening with just a few cirroform clouds across Sonora shifting eastward. Quiet weather will continue through the overnight with seasonable temperatures. No updates this evening. See previous discussion for additional information. && .AVIATION...Valid through 09/06Z. Mostly clear. SFC wind less than 12 kts through the period, with some afternoon gusts around 15 kts at KOLS and KDUG possible Thursday. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER...Expect dry conditions with occasional cirrus clouds into early next week. Daytime minimum relative humidity values will generally be in the 15-30 percent range, with slightly higher humidity values across the higher peaks. 20-foot winds will be terrain driven at less than 15 mph during much of the period into next week. However, there will be some afternoon gusty winds at times. A more easterly component should occur Friday into Saturday afternoon. Temperatures will cool into next week. && .PREV DISCUSSION...Long period troughiness across much of the U.S. will bring a slow cooling trend to SE AZ late in the week and into early next week. Otherwise relatively dry with precipitable water values near or below 1/2 inch. Surface dewpoints in the 30s this morning have cratered into the teens and 20s closer to the international border as northern Sonora and Southeast Arizona see a low level drying trend over the next 18 hours. The latest HRRR captures this well. A week westerly flow will bring in some patches of cirrus level moisture around Thursday or so, but still dry below that. Surface high pressure building down the front range of the Rockies and the Central Plains will bring a lower level southeasterly to easterly flow late Friday into Saturday. We might see dew points creep up along with this, but still relatively dry. It will make the early morning low forecast Saturday morning problematic as we see some locations with an easterly exposure fail to set up the normal early morning radiation inversion. With the boundary layer remaining mixed in those locations overnight temperatures will not drop as low, even as some nearby sheltered locations do. Additional energy carving into the back side of the CONUS mean trough position early in the new week will probably be far enough west for some gusty winds and more significant cold air advection. However, any significant moisture and dynamics will likely remain northeast and east of our area. && .TWC WATCHES/WARNINGS/ADVISORIES...None. && $$ Lader/Meyer/Powell Visit us on Facebook...Twitter...YouTube...and at