Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 03/23/18

Area Forecast Discussion...UPDATED
National Weather Service Albuquerque NM
512 PM MDT Thu Mar 22 2018 .AVIATION... 00Z TAF CYCLE Southwest to westerly flow aloft, strengthening considerably aft 23/12Z as upper trough passes just to the north of NM. Return flow may bring some low clouds to far se NM aft 23/07Z, with HRRR most agressive with the northern extent of this moisture reaching from KROW to near KCVS around 23/12Z. Potential for MVFR/IFR cigs/vsbys not reflected in the KROW TAF at this time as other models not so bullish. Otherwise, mts over nw and north central NM to become occasionally obscured aft 23/10Z with scattered -shrasn. Winds increase at the same time and shift to w-nwly as a cold front races from west to east over NM. Gusts to around 45kt possible over ern NM aft 23/18Z with lcl reduced vsbys in bldu. && .PREV DISCUSSION...252 PM MDT Thu Mar 22 2018... .SYNOPSIS... The warming continues today, with well above normal temperatures and a number of eastern plains locales challenging daily records. Clouds will spread across the state tonight and help to moderate temperatures Friday, except across the eastern plains where strong downslope winds will send temperatures soaring to near daily records once again at locales such as Roswell, Portales and Clovis. Strong winds will spread over the area Friday and result in very windy conditions across much of central and eastern New Mexico Friday afternoon and early evening. A stronger Pacific system will approach Sunday and create strong winds across much of the area once again. This system will move slowly east across the region into mid week and combine with a backdoor cold front to produce good chances for precipitation, peaking Wednesday and Wednesday night. Below normal temperatures will follow behind the backdoor cold front Tuesday through Wednesday. && .DISCUSSION... The warming trend continues with temperatures soaring well above normal this afternoon, especially across the eastern plains where downslope winds are helping highs rise to near daily record values. Clouds moving in from the Pacific will blanket the area tonight, with well above normal lows forecast and generally 5 to 10 degrees warmer than last night. A shortwave trough, currently moving across central/southern California, will race east overnight and across New Mexico tomorrow bringing a mix of clouds, showers and strong winds. Showers will focus across the northwest high terrain and will likely provide several inches of snowfall to the peaks and west-facing slopes of the Tusas Mountains. Strong winds will develop quickly Friday morning across much of central and eastern New Mexico and a Wind Advisory has been issued for much of that area. Clouds will help to moderate temperatures Friday, but stronger downslope winds will send highs soaring once again across the east central and southeast plains Friday afternoon where daily record values will be challenged. Although less than Friday, breezy to windy conditions are forecast Saturday in response to a stronger Pacific system approaching from the west coast. The forecast from Sunday through the middle of next week will be focused on the approach and progression of a deep upper low and the passage of a backdoor cold front. As the upper low approaches from over the Great Basin on Sunday, strong winds will spread over the state and a lee side trough will deepen to near 995mb over southeast Colorado. Chances for blowing dust to be an impact on Sunday are on the uptrend, with warm and unstable conditions expected. Temperatures will trend down from early to mid week, especially after the backdoor cold front pushes through on Tuesday and precipitation ramps-up. The 12Z operational runs of the ECMWF and GFS compare favorably through 12Z Tuesday, then begin to depart with the handling/progression of the upper low. The GFS has been consistently wetter and has support from both the GFS ensemble mean and the Canadian. Our forecast is titled toward the wetter GFS for Tuesday through Wednesday night for now given the run-to-run consistency and aforementioned other model support. If the 12Z GFS works-out we`ll be looking at significant snowfall in the mountains, especially along the east slopes of the central mountain chain thanks to upslope enhancement. In addition, the timing of the backdoor cold front into the Middle Rio Grande Valley Tuesday night combined with the position of the upper low over southeast Arizona would be favorable for one of the stronger east wind events we`ve seen here in quite some time. The 12Z GFS MOS for KABQ was alarmingly high with the wind speeds for Tuesday night and Wednesday, but we`ve seen this issue in the past with the seasonal change to the warm season MOS equations. 11 && .FIRE WEATHER... ...Critical fire weather conditions across the eastern plains Friday through Monday. Red Flag Warning is in effect for Friday afternoon into the evening... An upper level disturbance will move across northern AZ tonight and northern NM Friday. This system will bring light rain and high elevation snow to northwestern and north central NM tonight through Friday. Wetting precipitation is likely in the Northwest Mountains, especially in the Tusas Mountains, where 3 to 6 inches of of snow will fall. A strong Pacific cold front will move into western NM around dawn and then move rapidly eastward to the NM/TX border by late afternoon Friday. West to northwest winds behind the front will gust to around 40 mph along and behind the front west of the central mountains Friday morning through mid afternoon. To the east of the central mountains west to southwest winds will range from 30 to 40 mph with gusts up to 55 mph Friday afternoon and early evening. Critical relative humidity in FWZ104, FWZ107 and FWZ108 combined with very warm temperatures and strong winds will produce critical fire weather conditions Friday afternoon through early evening. A Red Flag Warning for these fire weather zones is in effect. Ventilation will be excellent across the entire area Friday. The upper level flow will turn to the southwest Saturday. Stronger southwest winds aloft Saturday afternoon will mix down to the surface from the south central plains north northeastward to the northeast highlands and northeast plains. The Haines index across these areas has trended upward with the forecast issuance, and afternoon relative humidity east of the central mountains will range from 10 to 15 percent. Critical fire weather conditions are likely from the central plains northeastward across the northeast plains Saturday afternoon and early evening. Ventilation will once again be excellent Saturday. Deepening surface low pressure in eastern CO Sunday and a strong band of 40 to 50 mph winds aloft Sunday will produce 20 to 30 mph winds with gusts above 40 mph at times across areas east of the central mountains. Drier air will also move into northern and central NM Sunday with afternoon relative humidity falling into the single digits across much of the area. Critical fire weather conditions appear likely Sunday afternoon and early evening across the eastern plains and adjacent highlands. Continued dry surface conditions and breezy southwest winds Monday across the eastern plains will continue the threat for critical fire weather conditions. Excellent ventilation is likely Sunday and Monday afternoons. A storm system currently off the southern British Columbia coast is forecast by the models to gradually move southward and into AZ by early Tuesday. This storm system will have the potential to bring wetting precipitation to northern and central NM Monday night through Thursday. 28 && .ABQ WATCHES/WARNINGS/ADVISORIES... Red Flag Warning from noon to 8 PM MDT Friday for the following zones... NMZ104-108. Wind Advisory from 11 AM to 7 PM MDT Friday for the following zones... NMZ513>515-523-526>535-539-540. && $$
Area Forecast Discussion
National Weather Service Duluth MN
746 PM CDT Thu Mar 22 2018 .UPDATE... Issued at 745 PM CDT Thu Mar 22 2018 The forecast was updated to account for the latest cloud trends. We increased clouds for several more hours over far northern Minnesota and over southwest half to third of the Northland. Drier air will gradually work it`s way across the area causing the clouds to diminish. There is still a concern some lake induced clouds will develop along the North Shore down into far western Lake Superior as the low level flow becomes more easterly tonight. Delta-T values are favorable for some cloud and possible light snow but the airmass is quite dry. The RAP continues to indicate very dry air over the lake through the night and into Friday morning. We`ll monitor through the night for any possible cloud development. && .SHORT TERM...(This evening through Friday) Issued at 321 PM CDT Thu Mar 22 2018 Surface and upper level ridging will cover the forecast area tonight and Friday. A mix of clouds and sun are affecting a large portion of the region this afternoon. This is due to an upper level vorticity maxima sliding overhead this afternoon. Look for the clouds to dissipate later this evening as the vort max departs. Clouds will be on the increase Friday afternoon ahead of the system that will affect a portion of the Northland Friday night and Saturday morning. .LONG TERM...(Friday night through Thursday) Issued at 321 PM CDT Thu Mar 22 2018 Upper level ridging remains over the forecast area Friday evening. However, an approaching upper long wave trof, with embedded pieces of vorticity, will move into western Minnesota late Friday night and linger Saturday morning. Meanwhile, its associated surface low will be moving through Kansas Friday night and into Missouri Saturday before dissolving. This combination will result in some mixed precipitation to affect the western third of the forecast area as early as late Friday afternoon through Saturday morning. Expect a rain/snow mix initially, changing to all snow overnight through Saturday morning before ending. The precipitation may reach as far east as the I35 corridor from Moose Lake to Rush City, before ending in all areas by Saturday afternoon. The greatest likelihood for snow accumulation will roughly be in the Brainerd Lakes region northwest to near Walker, where 1 to 3 inches of snow is probable. The upper trof washes out by Saturday afternoon allowing ridging to rebuild across the region. The ridging prevails through Sunday. Sunday night through Tuesday finds the region under the influence of a southwest flow aloft as a long wave trof moves ashore on the West Coast, reaching the western Great Lakes Tuesday. In response, a surface low develops in the Four Corners and moves into the Texas panhandle by Tuesday. An inverted trof from this low will reach the Northland Sunday night and affect the area through Tuesday. Look for another mixed precipitation event during this timeframe. Current thinking is rain and snow, as is typical with Spring systems. Will hold off on mentioning any amounts for now as confidence is low. && .AVIATION...(For the 00Z TAFS through 00Z Friday evening) Issued at 647 PM CDT Thu Mar 22 2018 An area of high pressure over the region will provide VFR conditions across most of the region tonight into Friday. The low level flow will become easterly overnight and drier air will cause clouds over far northern Minnesota and western portions of the Northland to diminish overnight. The clouds over the Borderland will still move south for a time this evening, reaching KHIB, but will then diminish overnight. A long fetch across Lake Superior will develop overnight as winds veer but the RAP shows the low level airmass remains quite dry so widespread lake induced clouds look unlikely at this time. Some MVFR clouds off of Lake Superior will be possible though late tonight and some flurries will be possible if they do develop. Easterly winds will increase through the day Friday and forecast soundings show mixing to at least 850MB will develop leading to gusty winds by afternoon for much of the area. && .PRELIMINARY POINT TEMPS/POPS... DLH 12 35 20 35 / 0 0 10 0 INL 15 41 19 39 / 0 0 10 0 BRD 18 41 26 39 / 0 10 60 40 HYR 11 42 22 41 / 0 0 10 0 ASX 9 37 20 38 / 0 0 0 0 && .DLH WATCHES/WARNINGS/ADVISORIES... WI...None. MN...None. LS...Small Craft Advisory from 4 PM Friday to 10 PM CDT Saturday for LSZ144>147. Small Craft Advisory from 4 PM Friday to 4 AM CDT Sunday for LSZ141>143. && $$ UPDATE...Melde SHORT TERM...GSF LONG TERM...GSF AVIATION...Melde
Area Forecast Discussion
National Weather Service Grand Forks ND
949 PM CDT Thu Mar 22 2018 .UPDATE... Issued at 948 PM CDT Thu Mar 22 2018 Still have mostly cloudy skies over the area, but there are a few holes here and there. There are also a few stations reporting fog, but it is still in the 3 to 5 mile range, which is not too bad yet. && .SHORT TERM...(This evening through Friday) Issued at 326 PM CDT Thu Mar 22 2018 Stratocu breaking up over NW MN and parts of E ND this aftn and trend should be some clearing thru the evening, esp east of the Red River. West of the Red River the persistent low level moisture should allow low clouds and some fog to reform. In clearer areas east of the Red River, patchy fog is also possible. Focus is then on Friday system and arrival timing. Short range models in good agreement on timing of snow eastward and used them to time snow arrival in hourly pop/wx grids into Friday night. The HRRR and RAP are a bit slower than the blended conshort and ECAM guidance used for pops however. Idea is for snow to move into the western fcst area mid morning....reach parts of the Red River valley in the mid to late afternoon. The band of snow will be orientated northwest to southeast. Temps ahead of the snow will be above freezing but will fall to or just below freezing as the snow moves in. Thus anticipating little liquid precipitation. Snow rates should be quite high for several hours, esp in central ND Minot-Devils Lake-Jamestown-Valley city region Friday aftn due to good overlay of low/mid level frontogenesis and upper level lift. Snow rates of 1-2 inch per hour psbl in this area where snow totals of 8 or more has the highest chance of occurring. .LONG TERM...(Friday night through Thursday) Issued at 326 PM CDT Thu Mar 22 2018 How far east will the heavier snow get before the lift/frontogenesis transitions a bit more into southern Minnesota Friday night. Northern Red River valley should see several inches but could possibly get more if the lift remains strong. For now went advisory mid/nrn valley. Snow will taper off western fcst area after midnight Friday night and could be replaced by some freezing drizzle as low level moisture remains but main seeding clouds move out. Warnings/advisories and snow amounts coordinated well among the neighbors for this event. Lingering snow and rain will be possible across far southeastern ND and west central MN early Saturday morning. As the bulk of the precipitation exits the region to the south and east through mid day Saturday, dry air aloft could cause the loss of ice nuclei over eastern ND. As this occurs areas of freezing drizzle will be possible. However, 10-15 mph southeast winds at the surface may mix and dry out the near surface layer, so impacts from freezing drizzle will likely be minimal. A second shortwave embedded in southwesterly flow aloft is expected to move into southern Canada on Sunday. This shortwave will bring a second round of snow to eastern North Dakota and much of northwestern and north central Minnesota. Snow is expected along and north of the Highway 2 corridor Sunday afternoon and evening. Further south, warm afternoon temperatures near and just above the surface will support a mixed precipitation type of rain and snow. The active pattern continues for Monday as a central Plains low moves eastward to our south. A daytime rain/snow mix and overnight snow will be possible across the eastern ND and northwest MN region Monday through late Monday night with the best chance for precip south of Highway 2 and across far southeast ND and western MN. Although there is low confidence in exact amounts, snowfall accumulation Sunday through Monday night will not be as high as the Friday storm system. However, as snowfall melts during the day and refreezes at night, along with light snowfall accumulation, roadways may be slick and hazardous during the morning and late evening hours during this period. Quiet weather will return mid week as a surface high builds over the northern Plains. Afternoon temperatures in the upper 30s and low 40s will help begin to melt weekend snowfall. && .AVIATION...(For the 00Z TAFS through 00Z Friday evening) Issued at 647 PM CDT Thu Mar 22 2018 Other than KDVL, ceilings have risen into the VFR range at the other TAF sites. Think this will remain the case for tonight into early Friday, when ceilings begin to lower again with the approach of the next winter storm system. There may be some patchy fog around again, but best chances may be at KDVL or KGFK. Overall confidence pretty low in that right now. Most of the latest model guidance holds off on any snow until around 20-21z Friday at KDVL/KFAR and an hour or two later at KGFK. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...Winter Weather Advisory from 4 PM Friday to 7 AM CDT Saturday for NDZ007-008-016-027-030-054. Winter Storm Warning from 1 PM Friday to 7 AM CDT Saturday for NDZ026-029-039-053. Winter Storm Warning from 10 AM Friday to 7 AM CDT Saturday for NDZ006-014-015-024-028-038-049-052. MN...Winter Weather Advisory from 4 PM Friday to 7 AM CDT Saturday for MNZ001-002-027-031. Winter Storm Warning from 1 PM Friday to 7 AM CDT Saturday for MNZ003-029-030-040. && $$ UPDATE...Godon SHORT TERM...Riddle LONG TERM...AM/Riddle AVIATION...Godon
National Weather Service Jackson KY
1103 PM EDT Thu Mar 22 2018 .UPDATE... Issued at 1055 PM EDT THU MAR 22 2018 Skies remain mostly clear to clear under high pressure with decoupling in valleys leading to some readings near 30 if not the upper 20s at this time with mid 30s on the ridges. These readings indicate that the lower min T updated to this evening appears to be on target. Uncertainty remains with the system this weekend as the 0Z guidance begins to roll in. Further analysis of the previous data seems to point toward a sharper temperature gradient from north or northeast to southwest with Fleming, Rowan, and Elliott counties remaining a category or so lower than blended model guidance and have followed these trends for temperatures on Saturday. 18Z GFS guidance and new 0Z NAM sounding point toward the column remaining the coldest in these counties. Latest trends seem to be toward a bit more accumulation in those locations and these counties were highlighted a refreshed SPS. As the remainder of the 0Z guidance comes in a better determination can be made on what headlines may be needed for portions of the region. UPDATE Issued at 845 PM EDT THU MAR 22 2018 Hourly temperatures have been freshened up based on observation trends. High pressure should bring mostly clear to partly cloudy skies tonight. MOS guidance points toward colder valley temperatures in the northeast and east compared to the previous forecast while LAMP guidance points toward ridgetop locations also a degree or two colder. At this time, have trended temperatures down a degree or two across the board with no other changes at this time. Lots of uncertainty remain with the system to affect the region late Friday night into Saturday especially with the thermal profile in the lowest few thousand feet. Model consensus is for the coldest profiles near 0C at the sfc and for several thousand feet aloft over Fleming, Rowan, and Elliott counties. The NAM has quicker warming aloft associated with the low level jet which would lead to melting and transfer of warmer air to the surface quicker. The GFS is colder, especially over northern Fleming County and this seems to be the most probable location for a couple of inches of accumulation. Whatever does fall will be battling rather warm ground and even limited solar insolation from late March sun should help inch temperatures above freezing in all locations by Saturday afternoon. && .SHORT TERM...(This evening through Friday night) Issued at 340 PM EDT THU MAR 22 2018 19z sfc analysis shows high pressure building more effectively into eastern Kentucky. This is helping to settle the winds some after a time of gustiness following the breaking of the inversion early in the afternoon. Additionally, the high is helping to keep the cu to a minimum out there - mainly found in the far east. With ample sunshine temperatures have climbed into the low to mid 40s while dewpoints remain in the low to mid 20s. The latest satellite images shows the substantial erosion of any snow cover due to the warmer temps and late March sun. The models are in good agreement aloft through the short term portion of the forecast. They all depict full-latitude, strong ridging through the High Plains at the start of the period with Kentucky in the midst of fast northwest flow. This ridge does break down quickly as it attempts to come east but runs into a blocking closed low trough centered over New England. This will allow more Pacific energy and moisture to stream through the Upper Midwest and then down southeast into Kentucky for late Friday into Saturday morning. The core of this energy will be strong enough to buckle the ridge over the Central Plains Saturday morning - the NAM is strongest with this and actually starts to close off a mid level low while the other models maintain open waves. This all slides southeast into the JKL area on Saturday. Given the model agreement have favored general model blend with a strong lean toward the details from the higher resolution NAM12 and HRRR throughout the period. Sensible weather will feature high pressure moving over the state tonight and off to the east on Friday. Expect a ridge to valley temperature split to develop tonight with widespread frost through the area and some patchy fog along the river valleys. High clouds will slowly arrive on Friday from the west as a warm front starts to take shape to the southwest. This boundary lifts into eastern Kentucky later Friday night with ample moisture and lift to generate pcpn through the CWA as it moves from southwest to northeast with time. The cold air will be tough to shift out of the way in the northeast parts of the area along with wet bulbing likely to lower temps further at onset of the pcpn. Accordingly, expect the pcpn to move in as snow generally north and east of a line from Irvine to Whitesburg. Gradually this line will shift northeast through the night with a mix with and switch to rain anticipated for much of the area by 12z Saturday. Locations generally along and north of Interstate 64 will likely stay as snow and an inch or so of accumulation will be possible by sunrise Saturday. The snow will continue into the morning in our far northern areas - but likely remain below warning criteria due to low snow ratios. For that reason will keep Fleming and Rowan out of the Winter Storm Watches current in effect to the north and instead issue an SPS highlighting this concern in addition to mentions in the HWO. Started with the CONSShort and ShortBlend for the bulk of the grids in the short term portion of the forecast. Did make some significant adjustments to temperatures tonight for relative elevation differences - especially northeast. As for PoPs, beefed them up in the south quicker Friday night into Saturday morning closest to the NAM12 scenario. .LONG TERM...(Saturday through Thursday) Issued at 325 PM EDT THU MAR 22 2018 The extended will feature a period of colder weather and the potential for accumulating snowfall to start things off, before transitioning into a much warmer weather pattern that will feature chances of rain the first few days of the new work week. An area of low pressure is forecast to move southeastward and across the Ohio and eastern Tennessee valley regions Friday night into Saturday. Rain will quickly transition to a rain snow mix and then to all snow Friday night. The snow is expected to move across northern portions of eastern Kentucky through late Saturday morning, before change back over to all rain by the afternoon. Some accumulations of snow will be possible, but there is some uncertainty at this time as to how much snow we will see. The current pattern does suggest that the bulk of any accumulating snow would occur north of the Hal Rogers Parkway. As the area of low pressure moves across the area during the warmer part of the day on Saturday, it may even trigger a few thunderstorms from the Tennessee border northward to the Hal Rogers Parkway, where warmer temperatures and a bit of elevated instability may exist. The rain should finally begin to taper of late Saturday night, as the low pulls away to the southeast. We will likely see some snow mixing with the rain Saturday night as well, as colder air makes a weak southward push. Little if any accumulation is expected from this second batch of snow. Any remaining precipitation should move out of eastern Kentucky by early Saturday evening. Temperatures are expected to be below normal over the weekend as a trough of low pressure aloft keeps colder air in place over the region. Once this trough moves away, as a ridge of high pressure settles over the region. An area of low pressure will also be in play to during this time, and could bring a few rain showers to the western portions of our forecast area, but isolated to scattered at best on Monday and part of Tuesday. Better chances of rain will be in the offing Wednesday and Wednesday night, as a frontal boundary moves across the area. This boundary may even stall for a bit, bringing enhanced rain chances to eastern Kentucky. Southerly flow associated with this front, and the ridge that will temporarily set up across the area in the days before the front arrives, will also bring warm air from the Gulf of Mexico into the region. This will allow temperatures to warm into the upper 50s to perhaps 60 on Monday, and into the 60s the rest of the week. && .AVIATION...(For the 00Z TAFS through 00Z Friday evening) ISSUED AT 835 PM EDT THU MAR 22 2018 High pressure at the surface and northwest flow aloft is expected through the period. Some mid level clouds are expected in the northwest flow tonight with an increase in low and mid level moisture after 12Z leading to some thickening and lowering cloud bases ahead of a warm front. Some light rain could reach the Lake Cumberland region including near KSME by the end of the period. However, MVFR is expected to prevail throughout the period with light winds. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...JP SHORT TERM...GREIF LONG TERM...AR AVIATION...JP