Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 02/10/20

Area Forecast Discussion
National Weather Service La Crosse WI
547 PM CST Sun Feb 9 2020 .UPDATE... Issued at 547 PM CST Sun Feb 9 2020 While there may still be a bit of light snow remaining over portions of Adams County, observations from the central part of Wisconsin indicate little in the way of visibility reductions remain. This implies that any remaining snow is very light and would cause any new or additional impacts. Plan to let the winter storm warning expire at 6 pm as scheduled. && .SHORT TERM...(This evening through Monday) Issued at 341 PM CST Sun Feb 9 2020 At 3 PM, the low pressure area responsible for the 8 to 11" snow band along the Interstate 90 corridor today was located east of the Wisconsin Dells. The highest snow total (10.5") so far was in Elba, MN (Winona County). Other than a few snow bands across western Wisconsin much of the accumulating snow has moved out of the area. At this time, any snow accumulations (up to 1") look to be confined to Adams and Juneau counties in central Wisconsin. Due to this snow, kept the Winter Storm Warning going for these counties. Elsewhere, the winter headlines were cancelled or expired at 3 PM. With there being a few reports of a light wintry mix and the models showing that the lift would be rapidly weakening this afternoon, opted to mention some patchy freezing drizzle in a Special Weather Statement which is in effect until 6 PM tonight. For tonight, skies will gradually this evening. The combination of clearing skies and light winds may result in the development of areas of fog overnight. This was included in the TAFS between 10.09z and 10.15z. Low temperatures tonight will be in the single digits below and above zero. On Monday afternoon, the clouds will gradually increase as a Canadian cold front approaches the area from northern and western Minnesota. High temperatures will be in the mid and upper 20s. .LONG TERM...(Monday night through Sunday) Issued at 341 PM CST Sun Feb 9 2020 On Monday night, scattered flurries will be possible as a cold front moves through the region. From Wednesday into Wednesday night, an arctic cold front will move southeast through the region. With their being limited moisture ahead of this front, snow amounts look to be generally less than inch. However, there are a few GEFS members which have snow totals of 1 to 2 inches. Behind this front, much colder temperatures move into the region. High temperatures on Thursday will be in the single digits and in the teens on Friday. Low temperatures on Friday morning will range from 10 to 20 below. A Wind Chill Advisory may be needed for this time period. && .AVIATION...(For the 00Z TAFS through 00Z Monday evening) Issued at 547 PM CST Sun Feb 9 2020 Local radar and observations indicate the remaining light snow has moved well east of both airports. The clouds lingering behind the snow have kept MVFR ceilings in place but satellite trends show these are moving to the east with both airports expected to scatter out and go VFR this evening. The main concern for the overnight hours is whether any fog is going to develop as an area of high pressure builds into the region. Forecast soundings are not much help this evening as they show the low levels remaining saturated all night long following the fresh snow. The 09.21Z RAP would suggest there will be around 5 knots at the surface with 10 knots or more just above the surface through the night. Some guidance is suggesting dense fog forming overnight but with the forecast winds, this seems unlikely and for now, have stayed with the idea that if fog develops only taking the visibility down to MVFR. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...None. MN...None. IA...None. && $$ UPDATE...04 SHORT TERM...Boyne LONG TERM...Boyne AVIATION...04
Area Forecast Discussion
National Weather Service Columbia SC
716 PM EST Sun Feb 9 2020 .SYNOPSIS... A dry surface ridge over the region will move off the coast Monday. As the high moves offshore moisture will again begin increasing as southerly flow overspreads the region ahead of the next frontal system. The front and associated high moisture are forecast to be in the region Tuesday. && .NEAR TERM /UNTIL 6 AM MONDAY MORNING/... High pressure will dominate the region overnight with high clouds crossing the region. Some potential for fog toward daybreak as moisture begins increasing however expect fog which develops to be patchy and mainly confined to fog prone areas. Winds have become light and variable and will remain so overnight resulting in temperatures falling into the upper 30s to low 40s. && .SHORT TERM /6 AM MONDAY MORNING THROUGH WEDNESDAY/... High pressure will provide The Midlands and CSRA with a dry and warm Monday. A frontal boundary moves into the region on Monday Night through Tuesday with periods of showers and a chance of thunderstorms. This boundary should lift a bit northward on Wednesday for somewhat drier conditions. It will be warm with highs in the lower to mid 70s and lows around 60. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... An upper trough pushes a frontal boundary through The Midlands and CSRA Thursday through Thursday Night with showers and thunderstorms. Will need to watch for the severe weather potential with the passage of this system. Canadian high pressure builds into the region Friday through Saturday with dry weather and much cooler temperatures. Models differ next Sunday with the GFS 24 to 36 hours faster with the next upper trough than the ECMWF. The consensus model blend results in a chance of showers. && .AVIATION /00Z MONDAY THROUGH FRIDAY/... High confidence in VFR conditions through much of the period although there is a possibility of fog/stratus during the predawn hours into mid morning. Surface high pressure centered offshore is ridging into the Carolinas this evening. Satellite imagery shows high clouds extending back to the southern Plains traversing the forecast area and this is expected to continue through the night and Monday. Model guidance suggests a 20-25 knot low level jet overnight which should be enough to keep some mixing in the boundary layer and this may favor more stratus than fog but confidence is limited. MAV/LAMP and HRRR generally not showing any restrictions but the NAM is showing LIFR restrictions all terminals, similar to last night. Will continue with a persistence forecast of VFR with tempo MVFR vsbys 09z-13z time frame. Winds will pick up from the southwest by late morning to around 8 to 10 knots with some gusts to 15-17 knots in the afternoon. EXTENDED AVIATION OUTLOOK...A series of weather systems will provide a chance of showers and associated restrictions at times Monday night/Tuesday and again Thursday. && .HYDROLOGY... Runoff from the recent heavy rainfall event is resulting in moderate to major flooding on all area river forecast points. Please stay abreast of the latest river stage forecasts on our webpage at && .CAE WATCHES/WARNINGS/ADVISORIES... GA...None. SC...None. && $$
Area Forecast Discussion
National Weather Service Duluth MN
854 PM CST Sun Feb 9 2020 .UPDATE... Issued at 854 PM CST Sun Feb 9 2020 Temps are overachieving along the Borderland and have surpassed prior forecasted min temps. Have dropped them a few more degrees. Once the southwest flow develops and affects this area, temps should stabilize, and possibly rise later. Added fog to Price County as its has covered much of the county. && .SHORT TERM...(This evening through Monday night) Issued at 310 PM CST Sun Feb 9 2020 An area of low pressure centered well south of the Northland will continue to move east and high pressure will build in behind it. Dry conditions are expected for most areas tonight but there are some questions on cloud cover and most areas have cleared out this afternoon. We increased clouds later tonight, especially over the western half of the Northland. The RAP and NAM both show low level RH values increasing tonight, especially in the 900-925MB layer. There were areas of stratus over western Minnesota and eastern North Dakota and we expect that will fill back in and expand to the east as low level winds back tonight. Confidence in how widespread clouds will be tonight is lower than average and cloud coverage will have a big affect on temperatures. We have lows from the single digits above to the single digits below for now but if skies remain cloud free longer than expected tonight, they will likely not be low enough. A shortwave will arrive on Monday and move through the Northland into Monday night. We expect light snow to become likely for much of northern Minnesota with a chance further south or flurries. Snow amounts are expected to be light with most areas receiving less than an inch. .LONG TERM...(Tuesday through Sunday) Issued at 310 PM CST Sun Feb 9 2020 The extended will feature a couple opportunities for light snow with an arctic front coming through Tuesday night into Wednesday. Tuesday will be a dry day with temperatures in the twenties thanks to weak low level ridging. However, a strong cold front will move through the Northland Tuesday night into Wednesday ushering in much colder air and bringing a chance for light snow. The GFS remains a bit faster than the ECMWF with the front but the models are in pretty good agreement. Light snow will spread north to south Tuesday night into Wednesday with mainly light accumulations expected. There will be a period Wednesday as winds become northerly that some heavier snow will occur along the South Shore but drier air quickly moves over the lake by late afternoon/early evening. Most areas will see a dusting to perhaps 2 inches with the frontal passage. High pressure will build into the region Wednesday night into Thursday bringing an end to light snow chances. Temperatures will be cold enough and winds high enough to produce wind chills of 25 to 35 below zero Wednesday night over much of central to northern Minnesota and Wind Chill Advisories will likely be needed. Highs Thursday will only recover to 2 below zero to the single digits above. Another couple of shortwaves will bring light snow chances back to the region Friday into the weekend. Snow amounts should be light with some possible lake enhancement along the North Shore on Friday. Temperatures will also gradually warm late week reaching the upper teens to mid twenties over the weekend. && .AVIATION...(For the 00Z TAFS through 00Z Monday evening) Issued at 542 PM CST Sun Feb 9 2020 VFR at the outset with high pressure nearby. As the high drifts off to the southeast tonight, a southwesterly flow will develop and IFR clouds will form and spread across the terminals after 06Z. A cold front will affect the terminals after 18Z with the wind turning to the northwest and some light snow developing. Some vbsy restrictions into the MVFR range are expected near INL. On either side of the front, gusty winds will affect the terminals through the end of the forecast. && .PRELIMINARY POINT TEMPS/POPS... DLH 4 25 14 24 / 0 60 60 0 INL -11 28 10 24 / 10 80 60 0 BRD 4 27 13 25 / 0 40 30 0 HYR -5 29 15 27 / 0 10 20 0 ASX 2 30 17 27 / 0 20 40 0 && .DLH WATCHES/WARNINGS/ADVISORIES... WI...None. MN...None. LS...None. && $$ UPDATE...GSF SHORT TERM...Melde LONG TERM...Melde AVIATION...GSF
Area Forecast Discussion
National Weather Service Fort Worth TX
705 PM CST Sun Feb 9 2020 .SHORT TERM... /NEW/ Update: The overall environmental setup has remained relatively unchanged from previous forecasts, as outlined in the earlier short term discussion included below. However, a couple of subtleties appear to be working against more widespread convective development than what`s currently observed as of 630pm. There are still two main areas of concern, one being the area of strong warm advection near/east of I-35 that has supported a broad area of shallow showery activity, and the second being the cold front arriving from the northwest. Both areas will be monitored for robust convection through the next ~8 hours or so, although our window of diurnal destabilization aiding in surface-based convection has begun to close. First Area - Prefrontal warm advection activity: Shallow convection beneath a weak capping inversion sampled by the 20z and 00z FWD soundings continues near and east of I-35 this evening. This area was socked in with clouds and light rain all afternoon, and diurnal destabilization suffered as a result. While ascent via warm advection has been strong, warm advection`s effect on the cap appears to have won out thus far, with an inversion still present around 725mb. Low-level lapse rates have remained marginal as a result, and a lack of buoyancy through the lowest 3 km is likely impeding parcel ascent. It appears less likely that much in the way of deep convection will be able to develop in this region over the next few hours, but trends will continue to be monitored. Strong shear supportive of rotating updrafts exists in this region, and some low-topped supercellular structures would be the main storm mode if deeper convection was to initiate. While open warm sector convection in that type of environment would tend to support some tornado threat, decreasing surface-based buoyancy heading into the evening appears it would keep this threat minimal, should deep convection be able to develop at all. Second Area - The Cold Front: Forcing immediately along the frontal boundary has resulted in a thin corridor of convection. This activity is quickly becoming undercut by the advancing front, but as storms become elevated, they`ll retain a potential to produce some hail, most of which should be below severe limits. Areas across the far western CWA are lacking moisture, as dewpoints had mixed into the upper 50s this afternoon. But as the front enters the I-35 corridor with greater moisture content, am expecting some development farther southwestward down the boundary with upscale growth occurring. The steepest lapse rates in the 500-700mb layer vaguely coincide with the greater moisture content as well, and the I-35 corridor eastward should have the greatest chance of seeing a strong or borderline severe storm yet this evening, although this threat will remain isolated. Otherwise, the cold front will move through the entire area on schedule, clearing the region to the southeast tomorrow morning. A much cooler, cloudy, and periodically rainy day will follow for Monday as strong upglide accompanies an upper shortwave above the cold post-frontal airmass. Some elevated instability will exist above the frontal surface which could support isolated elevated embedded thunderstorms on Monday afternoon and evening, mainly south of I-20. Severe weather is not expected with any of this activity. -Stalley Previous Discussion: /This Afternoon through Monday/ The main concern through the late evening hours will continue to be the conditional threat for severe weather. A prolonged period of deep southerly flow has transported rich Gulf moisture northward and latest observations indicate that 65 degree dewpoints have made it nearly to I-20. With extensive low cloud cover, temperatures have struggled to climb out of the lower 60s in most locations, but visible satellite imagery does show some scattering of clouds west of I-35 as a result of deeper mixing. Scattered showers will continue through the afternoon hours in the strong warm advection regime mainly east of I-35. A deep upper trough is digging through California today and as it does a strong cold front is sliding southward through the Plains. It is currently located across West Texas and stretches northeast across Central Oklahoma and will continue to make steady south progress through the afternoon, perhaps entering our northwest counties by sunset. Ahead of the front in the warm sector, we`ll continue to monitor the potential for thunderstorms to develop, aided by a weak mid level impulse spreading out of northern Mexico. The HRRR continues to be the most aggressive guidance in developing discrete convection well ahead of the cold front late this afternoon and evening. While this is certainly possible, there remains quite a bit of uncertainty. The 12Z FWD sounding didn`t have a strong capping inversion per se, but did have a deep warm layer between 850-600 mb. This is likely to cool and lift some through the afternoon, especially if the upstream impulse is stronger than currently forecast. Continued warming of the surface through the afternoon, especially if we see any breaks in the cloud cover, could yield parcels which are able to convect within the warm advection regime. It is in this warm sector (generally from Waco to Fort Worth to Gainesville and areas east) that we are most concerned through the evening hours, as shear profiles are quite strong in the lowest 2.5 km. Surface based parcels ingested into a strong updraft would certainly have the potential to rotate and supercell storms would be possible with a hail/tornado threat. If deep convection fails to initiate in the warm sector, then there is certainly still a severe threat with any storms that develop along and just ahead of the southward moving cold front tonight. Mid level lapse rates will steepen through the late evening hours and ample deep layer shear will persist to support supercell structures - perhaps elevated - with a large hail threat. This threat would likely continue until about midnight before the cold air deepens and we lose better instability. The front will continue to move southward overnight, clearing the region during the early morning hours. Moisture and clouds will linger through the day on Monday as southwest flow will remain in place atop our colder airmass. Another upstream disturbance will swing across West Texas during the day and additional areas of rain are expected to develop. The best chances are expected to be across the southern half of the region through the evening. No severe weather is expected tomorrow. Dunn && .LONG TERM... /Issued 443 AM CST Sun Feb 9 2020/ /Monday through Next Weekend/ --Potential Impacts: Multiple days of rain may result in an increased flood threat Monday afternoon through Wednesday morning. A Flash Flood Watch may be warranted for this timeframe in the coming days; however, there is still uncertainty as to the precip amounts and the locations where the heaviest precip will fall. Any location may be susceptible to flooding, but the greatest potential ATTM is in areas both east of I-35 and south of I-30. --Meteorological Details: The extended portion of the forecast picks up with the leading edge of a cold front making its way through the far southeastern portions of the forecast area around daybreak Monday. Showers and thunderstorms are likely to be ongoing across Central and East Texas in the vicinity of the front. Behind the front, a cold and shallow airmass will have settled into North and Central Texas accompanied by cloudy skies and breezy north winds. As the front undercuts the warm/moist Gulf air that has been transported into the area tonight and later today, it will promote isentropic ascent overtop of the cool airmass. Meanwhile, a longwave trough and pseudo cut-off low will develop over the Desert SW of the CONUS. With the northern branch of the Polar Front Jet and mid level baroclinic zone remaining well north, the leading edge of the cold front is forecast to stall out just south of the forecast area Monday afternoon and remain there for a couple days. With isentropic ascent continuing overtop of the cool airmass, the low levels will be primed to produce precipitation with any weak lift that moves overtop. A weak shortwave trough is forecast to eject out of the longwave trough Monday afternoon, which should redevelop scattered to widespread rain showers. Most of the precip will fall as light to moderate rain, with only a few embedded storms across parts of Central and East Texas where more positively buoyant air will reside closer to the surface front. The next shortwave trough should approach the region over the course of the day Tuesday, again redeveloping scattered to widespread showers across the region. Finally, the strongest in the sequence of troughs should move through late Tuesday into Wednesday. This final trough will be accompanied by the Polar Front Jet and mid level baroclinic zone. The increased baroclinicity will induce cyclogenesis along the trailing edge of the stalled out cold frontal boundary over South Texas Tuesday and Tuesday night. Where the front and newly induced low are will be pivotal in the precip forecast Tuesday night into Wednesday. To the immediate north of the deepening surface low, a precip maximum is expected to develop. Guidance has indicated a band of 1-3+ inches of rain falling in a 12-hour period; however, the location of this has wavered north and south with each run and model. As with all newly developed systems, guidance will continue to struggle with the location of this low until tomorrow night`s front eventually stalls out across South Texas...then, forecast confidence can grow as to where this maximum will develop. Regardless of where this low develops, once the mid level trough moves east of the region, large scale subsidence and isentropic descent will finally take hold of the region Wednesday and Thursday. This will work to clear the clouds out of the region with some locations across the Big Country seeing the sun as early as Wednesday afternoon. The entire forecast area should receive abundant sunshine Thursday and Friday as a surface high pressure system moves into and through the area. As the surface high shifts east late Friday...return flow will setup across the area next weekend. NAEFS and ECMWF ensemble mean guidance is in firm agreement with the development of another deep longwave trough across the western CONUS next weekend and early next week. This will leave North and Central Texas under a similar pattern next week, with several weak shortwave perturbations moving through. Bonnette && .AVIATION... /NEW/ /00z TAFs/ MVFR conditions currently exist roughly from the I-35 corridor eastward. While a couple airports around the Metroplex have briefly scattered their low cigs, this should be short-lived, and cigs below 2 kft will be the prevailing condition. Have backed off on convective mentions in the TAFs with this issuance given observational trends, though a brief window of VCTS is still warranted as a cold front passes through later this evening. Post- frontal stratus should be present afterwards with northwest surface winds of 10-20 kts. Borderline MVFR/IFR cigs should continue into Monday and through the remainder of the TAF period with intermittent rainfall. Have included VCSH in the extended portions of the TAFs through Monday afternoon and evening, but this timing will be refined in subsequent forecasts with the introduction of RA/SHRA becoming necessary. -Stalley && .PRELIMINARY POINT TEMPS/POPS... Dallas-Ft. Worth 45 48 41 46 40 / 70 60 30 80 80 Waco 49 51 42 49 42 / 70 80 40 90 90 Paris 47 48 43 47 41 / 90 50 30 70 80 Denton 43 45 39 44 38 / 60 60 30 70 80 McKinney 44 47 40 46 40 / 90 60 30 80 80 Dallas 46 49 42 47 41 / 80 60 30 80 80 Terrell 48 49 42 49 43 / 90 60 40 80 90 Corsicana 52 52 44 51 45 / 80 80 40 90 90 Temple 52 54 43 49 43 / 60 90 40 80 90 Mineral Wells 42 46 36 43 36 / 40 60 30 80 80 && .FWD WATCHES/WARNINGS/ADVISORIES... None. && $$ 26
Area Forecast Discussion...UPDATED
National Weather Service Reno NV
713 PM PST Sun Feb 9 2020 .UPDATE... Have cancelled the Lake Wind Advisory for Pyramid Lake this evening since the gusty northeast winds experienced this afternoon have decreased below advisory criteria over the lake. Northeast winds will be breezy for the remainder of the evening with the possibility of blowing dust, reducing visibility around the region. Northeast winds will continue to be gusty for the Tahoe Basin through this evening, decreasing overnight. As for the Sierra crest into Mono County, expect these strong winds to last into Monday with gusts exceeding 100 mph at times. The Mammoth Mountain summit is currently seeing gusts of 145 mph! Winds are forecast to decrease in intensity along the Sierra crest by Monday night. -LaGuardia && .PREVIOUS DISCUSSION... /Issued 211 PM PST Sun Feb 9 2020/ SYNOPSIS... Gusty winds and brisk conditions will continue through Monday for much of the Sierra and western Nevada, with areas of blowing dust and choppy lake conditions. Unusually strong east to northeast winds along the Sierra continue through early Monday with turbulence along and west of the crest as well as increased potential for wind damage. Cold and dry conditions will persist for most of the week. Next disturbance with light snow showers is expected to move through the region Thursday night into Friday. SHORT TERM... The well advertised strong east wind event continues over the region into Monday morning, bringing strong winds to the Sierra ridges and hazardous conditions for air travel and area lakes. We did see some light snow accumulation this morning in the Sierra, generally a couple inches or less, but overall very light due to the lack of moisture. The unusually strong east winds have definitely been the main player. The peak wind of the day so far was at the top of Kirkwood Ski Area with a gust of 209 mph at 7:45AM this morning. If this observation is verified as accurate, then that could be the new California all-time record strongest wind! This is an unofficial measurement until it is certified as accurate by the California State Climate office. There are other locations around the Tahoe region Sierra Crest which are also seeing high winds, but not to the full extent of Kirkwood, most other stations are around 90-130 mph. There have already been a few reports of blown down trees around the Kirkwood area, and after the winds subside it is possible that we will get more reports of damage and we will make sure to document those. We also increased winds for Lake Tahoe through this evening, with expected gusts up to 50-60 mph on the lake with waves up to 3-6 feet especially along the western shores of the lake. These high waves are life threatening for anyone who ventures out onto the water today in a small boat. Minor lake shore flooding is likely with this high of surf and the current high lake level. Winds will continue to increase into Mono County and Mammoth Lakes areas through this evening. The Mammoth Mountain area will see winds steadily increase into tonight with potential for gusts to 150 mph. Wind damage to trees and power lines is possible for the Mammoth area this evening and tonight, especially for the higher elevations. Blowing dust continues around the region through tonight, mainly downstream of the Carson/Humboldt Sinks and downwind of the Smoke Creek/Black Rock/Honey Lake Basin. There is even some blowing dust even making it into the Tahoe Basin if you can believe that! How often have we ever talked about blowing dust in the Tahoe Basin? Winds will begin to diminish by Monday afternoon, but breezy east winds will continue in the Sierra ridges through Tuesday morning with brisk conditions and very low wind chills below zero. -Hoon LONG TERM...Tuesday through next weekend... Skies will clear out and we will see temperatures rebound back to above normal once again by Tuesday. Mild weather with mostly clear skies and light winds are expected Tuesday through Wednesday, with some increasing winds on Thursday ahead of the the next frontal system. The next storm system is expected to push through northern CA/NV Thursday night into Friday. This will bring gusty winds to the region and chances for mountain snow and valley rain. Temperatures will cool off sharply for Thursday with highs in the mid 40s for western Nevada and 30s in the Sierra. Another fast moving disturbance may move through the region next weekend, so we have kept in a chance of precipitation for then as well. There is quite a bit of spread in the models for next weekend, so still pretty low confidence there. -Hoon AVIATION... Rough day for flying across the region with impressive NE winds creating severe mountain wave turbulence and wind shear, and now areas of blowing dust. Models showing 80-100kt 500mb flow across the region through 12z/Mon as deep upper low dives into SoCal. This will continue the concerns for severe turbulence and wind shear into Monday morning, especially at our mountain airports such as TRK, TVL, and MMH. Worst conditions near MMH roughly 0z-7z this evening, with another burst of NE flow around TVL, TRK between 3z-9z tonight. For RNO, CXP, MEV, NFL gusty NE winds will persist into the evening with gusts up to 30-35kts likely, before fading tonight following latest HRRR guidance. This will bring in pockets of blowing dust but not anticipating anything below MVFR levels for periods of time. Pretty quiet tomorrow wind-wise with light NE flow. This pattern lasts into Tuesday and Wednesday as upper ridge builds in. -Chris && .REV Watches/Warnings/Advisories... NV...Wind Advisory until 4 AM PST Monday NVZ002. CA...Wind Advisory until 10 AM PST Monday CAZ073. Wind Advisory until 4 AM PST Monday CAZ072. && $$ For more information from the National Weather Service visit...