Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 11/02/22


Area Forecast Discussion
National Weather Service Goodland KS
528 PM MDT Tue Nov 1 2022 .SHORT TERM...(This evening through Friday Morning) Issued at 240 PM MDT Tue Nov 1 2022 RAP analysis shows textbook split upper level flow across the central plains resulting in virtually clear skies across the area. At the surface a low pressure system is located off of the Front Range. Winds are slowly creeping up across the area as diurnal mixing is a occurring. The strongest winds are across eastern portions of the area where a tighter pressure gradient is located. Temperatures are well above normal as the entire area is in the 70s and a few record highs may be in jeopardy through the afternoon. The Red Flag Warning continues for Kit Carson and Yuma counties as RH values have fallen below 15% thanks in part to the warm temperatures. Into tonight, overnight lows will be above normal in the upper 30s to low 50s. A mix of breezy SW winds and a LLJ will keep winds breezy overnight allowing the air to mix beneath the overnight inversion allowing temperatures from falling; some cloud cover moving west to east will also help keep temperatures warm. There are some hints at fog developing across Hitchcock and Red Willow counties overnight with a surface high located in the Nebraska Panhandle. I am somewhat skeptical of the fog potential due to the dry air advecting in so will leave out of the forecast for now. Into Wednesday, continued WAA and dry air moves into the area with breezy SW winds. Another day of near record to record high temperatures is expected as high temperatures are expected to be in the mid 70s to low 80s. Portions of the inherited Fire Weather Watch (along and south of Interstate 70) has been upgraded to a Red Flag Warning for Wednesday afternoon with winds of 35-40 mph expected. The counties north of I-70 that were in the Fire Weather Watch as confidence was not high enough to warrant issuing as concerns about wind duration remains. Another night of above normal overnight lows is expected with low temperatures in the upper 30s to mid 50s across the area. Locales in the eastern CWA may approach record lowest high temperatures. Thursday, continues to be a difficult forecast as guidance struggles with the evolution of the system. The GFS has speed up the trough while the ECMWF continues to alternate between solutions. The 12Z run of the GFS moves the dryline significantly eastward out of our area by 18Z which would eliminate severe weather potential. I don`t want to completely go all in on this solution as it seems like in the past with deep troughs the dryline seems to fluctuate on position in guidance. If a severe storm were to form it would be located in eastern portions of the area (Graham, Gove counties). Any storm would be fast moving, but all hazards would continue to remain possible. Forecast soundings continue to show gusty winds across the area with 40-50 mph expected. GFS continues to signal for blowing dust potential along and south of Interstate 70 based on office research criteria. There may be some fire weather potential if a slower frontal passage occurs as temperatures will be able to warm even more. If a fire were to develop it may be obscured by dust creating a potentially more hazardous situation. High temperatures for the day are currently forecasted to range from the lower 60s to mid 70s across the area. I opted to go with NBM for temperatures due to the overall uncertainty with the synoptic features, so the temperatures may fluctuate in upcoming forecasts. Thursday night and into Friday morning, confidence increased a bit in the potential for some light snow/wintry mix mainly across Yuma and Kit Carson counties. Overall snow accumulation looks to remain minimal due to the warm soil conditions still but elevated surfaces may become slick. Winds will continue to remain breezy overnight with increased pressure rises behind the front and especially as the stronger CAA moves into the area which may lead to reduced visibilities in areas of snow. Overnight lows will fall to the low 20s to mid 30s across the area. .LONG TERM...(Friday through Tuesday) Issued at 1250 PM MDT Tue Nov 1 2022 The long term is forecasted to have near to below average temperatures and a few chances for precipitation as a few upper level troughs move across the Western and Central CONUS. Friday is forecasted to start out cold and dreary in the wake of the front that moved through the prior night. While the heavier precipitation should move further south and east with the better synoptic forcing, light rain and snow would be possible for the morning hours and potentially through the afternoon as well as the column of air is forecasted to be saturated below the mid-levels. While ensemble spreads show near equal chances for the upper trough to either swing through to the east faster or slow down and deepen, increasing confidence in moisture and light precipitation is leading towards forecasting lower temperatures for the area on Friday. Current forecast is now closer to 40 and even lower temperatures could be possible if the trough deepens and drags more cold air south while cloud cover holds. If the trough moves through faster or cloud cover breaks, highs closer to 50 would be more likely. The weekend then sees more zonal flow aloft as heights rise before the next trough moves into the Northwest CONUS. With this, warmer temperatures are expected as 850mb temps begin climbing back toward the mid teens though will need to see how much moisture lingers as cloud cover could prohibit full heating and mixing. Currently keeping forecasts around the 60`s, though 70`s could be possible Sunday with lesser chances for moisture to linger that day. It is also worth noting that eastern portions of the area could be cooler, especially on Saturday when wrap around cloud cover and precipitation would be possible as a surface low moves off to the east with the upper trough. For next week, another trough is forecasted to move into the Northwest CONUS and make its way east though there is variance on timing and if a shortwave will precede the main trough. Currently leaning toward the slower solution with a shortwave based on 500mb ensemble spread charts showing some ensemble members with that solution. With this, temperatures will generally be near to above average except if the shortwave moves through which could allow for precip and cooler temperatures for a day early in the week. Will also have to watch for strong winds next week ahead of the main trough. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday evening) Issued at 526 PM MDT Tue Nov 1 2022 VFR expected to prevail at KMCK through the TAF period. Low level jet will result in low level wind shear late tonight through Wednesday morning, then some of those gusts mixing to the surface by mid Wednesday morning. && .CLIMATE... Issued at 240 PM MDT Tue Nov 1 2022 November 1st Maximum Temperatures Records: Goodland... 79 degrees in 1915 McCook... 82 degrees in 1990 Burlington... 78 degrees in 2017 Hill City... 81 degrees in 2015 November 2nd Maximum Temperatures Records: Goodland... 81 degrees in 1931 McCook... 79 degrees in 2005 Burlington... 81 degrees in 1931 Hill City... 83 degrees in 1931 && .GLD WATCHES/WARNINGS/ADVISORIES... KS...Fire Weather Watch Wednesday afternoon for KSZ001-002. Red Flag Warning from noon to 6 PM MDT Wednesday for KSZ013-014- 027-028-041-042. CO...Red Flag Warning until 6 PM MDT this evening for COZ252-253. Fire Weather Watch Wednesday afternoon for COZ252. Red Flag Warning from noon to 6 PM MDT Wednesday for COZ253-254. NE...Fire Weather Watch Wednesday afternoon for NEZ079>081. && $$ SHORT TERM...Trigg LONG TERM...KAK AVIATION...024 CLIMATE...Trigg
Area Forecast Discussion
National Weather Service Grand Rapids MI
755 PM EDT Tue Nov 1 2022 LATEST UPDATE... Aviation .DISCUSSION...(This evening through next Tuesday) Issued at 307 PM EDT Tue Nov 1 2022 - Fog expected again tonight - Tonight I expect fog to redevelop across the area. I have noted over the past year or so that when the RAP model and NAM4KM show dense fog in the same place at the same time it just about always happens as those models suggest. This has happened several times during the past 7 days. Every time it has happened we did get the dense fog that was suggested by those models. Given that, and knowing we will a surface high over us tonight allowing light winds with otherwise clear skies, it make sense to think of fog as a good possibility. Beside that the NAM, RAP, and HRRR all show the classic fog signature in there model soundings. The specific humidity increases with height over most of our CWA overnight. That is another classic fog signature. However, unlike last night the depth of the fog is expected to be shallower. Beside that it is now November the sunshine is not enough to really dry the low levels out like in September. All of these things lead me to believe we will have fog again tonight. While it will be colder tonight than last night, I still do not see much threat for freezing fog as it likely will not be quite that cold. The fog that does develop should mix out again tomorrow as it did today leaving us with a warmer than normal November day. - Warmer than normal into next week Our overall long wave pattern features a western trough and eastern ridge. While shortwaves will continue to track through the western trough over the top of the eastern upper ridge, the overall pattern should remain unchanged, at least into the middle of next week. This will keep the polar jet stream north of Michigan into at least the middle of next week. That in turn keeps us with above normal temperatures. Just ahead of each cold front, expect a surge of warmer air, so at this point I would expect Saturday to be the warmest day in the next 7 days. Yet another surge of warm air is likely with the front behind that. This should mean another fairly warm day during the middle of next week. It is possible we could break some record warm low temperatures Friday and Saturday with our forecast suggesting lows in the mid to upper 50s, which is about where our record warm lows are. While our actual forecast would not suggest record highs are possible even so our forecast highs may be a touch conservative. - Several large scale storms heading our way Saturday and beyond We have several storms to watch for in the next week or so. First we have a system that tracks north and west of us on Friday. That pushes the cold front our way. However, that cold front will likely not get close enough to bring showers here Friday. Meanwhile a strongly digging shortwave rounds the base of the western upper trough and sends a negative tilt upper shortwave our way for Saturday. That will bring some showers but more likely gusty winds, maybe a wind advisory. Yet another stronger Pacific system has to dig into the long wave trough and head our way for the middle of next week. That will be one to watch too. The Saturday system will not bring much cold air with it as the polar jet stays north of us yet. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday evening) Issued at 755 PM EDT Tue Nov 1 2022 The only thing keeping us from VFR through the 24 hour forecast is a medium to high potential for LIFR fog late tonight into mid Wednesday morning. With clear skies and light/calm surface winds overnight, radiational cooling and falling temperatures will support areas of fog formation despite some drier air that mixed down earlier this afternoon. A number of higher resolution models have been showing a shallower fog/cloud layer than previous nights, but a more pronounced surface inversion with specific humidity increasing with height in the lowest 200 feet. Visibility temporarily falling below minimums is possible during the pre- dawn hours, though some 10 to 15 knot southwesterly winds above 200 feet may delay thicker fog maintenance until late in the night. That and some recent runs of the HRRR have been less bullish, so have opted to keep prevailing quarter-mile visibility out of the TAFs for now. && .MARINE... Issued at 158 PM EDT Tue Nov 1 2022 The fog has mixed out however it is expected to return again tonight. A land breeze will help bring the fog into the near shore waters once again. Like today it will also mix out by late morning once again. Marine headlines are likely from Thursday into Sunday. The frontal system moving in from the west will increase winds into the 15 to 25 knot range with the strongest winds over the northern part of the lake during the day Thursday. The front then stalls west of Michigan and frontal wave strengthens and tracks northeast along that front, just west of Lower Michigan on Saturday. This could bring gales during the day Saturday. Once that system tracks northeast of the area the next upstream system will keep winds in the 15 to 25 knot range through Sunday. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...None. LM...None. && $$ DISCUSSION...WDM AVIATION...CAS MARINE...WDM
Area Forecast Discussion For Western SD and Northeastern WY
National Weather Service Rapid City SD
448 PM MDT Tue Nov 1 2022 .DISCUSSION...(This Evening Through Tuesday) Issued at 220 PM MDT Tue Nov 1 2022 20z surface analysis had low over western MT with lee trough into eastern CO. Tight pressure gradient ahead of it supporting gusty south/southwest winds across the CWA. Water vapour loop had upper trough of interest off the northwest CONUS coast with upper ridge over the northern Plains. Cirrus blobs spilling into northwest half of CWA, but where sunshine reigns temperatures have blossomed into the 70s. Evolution of upper trough main forecast concern. Tonight through Thursday, upper trough moves eastward as it splits. Main energy dips into the southwest CONUS with northern wave moving into south-central Canada. MT surface low/lee trough will be maintained tonight/Wednesday morning. 40-50kt low level southwesterly jet develops overnight into Wednesday morning. NBM4.1 50kt wind gusts probability fairly low, but setup looks really good given pattern recognition. Downslope enhanced flow over the northern Black Hills late tonight/Wednesday morning. Would like to see greater pressure gradient across the Black Hills (forecast 3-4mb) for higher confidence in 50kt wind gusts, but forecast soundings support high wind warning as well as HRRR guidance. Have hoisted headlines to account. Surface low moves east late Wednesday night dragging sharp cold front through the CWA with gusty northwest winds behind it. Wind advisory speeds possible, especially just east of the Black Hills per ensemble members. Will hold off on headlines until areal coverage becomes clearer. Cold front will be moisture starved, but eventually saturation will occur late Wednesday night into Thursday as post frontal low level frontogenesis combines with left exit region of 130kt jet streak. Should see a band of mostly snow across northeast WY/northern Black Hills slip into far southern SD late Wednesday. 1-3" snow accumulation looks reasonable for parts of northeastern Wyoming/northern Black Hills per 25-75th percentile computations. Lesser amounts near the NE border. Temperatures tonight will be quite warm over the downslope terrain areas. Highs Wednesday will be near guidance with 60s in the west and 70s in the east. Thursday highs will be 30-40F lower. Friday/Saturday, most ensemble solutions show a warming trend, but then another sharp cold front moves through Sunday. Temperature spreads 10-20F early next week, so confidence much lower, but trend has been of winter-like temperatures with some chances for light snow. && .AVIATION...(For the 00Z TAFS Through 00Z Wednesday Evening) Issued At 447 PM MDT Tue Nov 1 2022 VFR conditions are expected through the period. Gusty southwest winds will continue across portions northeastern WY and the northeastern foothills tonight. There is a wind shear threat tonight into Wednesday morning across the less windy portions of northeastern WY, the Black Hills, and portions of the western SD plains, including KRAP. Low level mixing after sunrise on Wednesday will then bring those gusty southwest winds down to the surface by mid to late morning. Winds will diminish late Wednesday afternoon. && .FIRE WEATHER... Issued At 220 PM MDT Tue Nov 1 2022 Southwest winds ahead of a developing low pressure system, coupled with very dry air and warm temperatures, will support critical fire weather conditions over the area through Wednesday evening. The strongest winds are expected over northeast WY into far western SD, where gusts over 50 mph will be possible, especially later tonight into Wednesday. Daytime RHes will fall into the teens. Poor RH recovery tonight. A cold front will move through the region Wednesday evening with increasing chances for mainly snow late into Thursday. A couple inches of snow accumulation over northeast WY/northern Black Hills. Much cooler and unsettled weather can then be expected into next early next week. && .UNR WATCHES/WARNINGS/ADVISORIES... SD...Red Flag Warning until 9 PM MDT Wednesday for SDZ319>335. High Wind Warning from 4 AM to noon MDT Wednesday for SDZ012-024- 025. WY...Red Flag Warning until 9 PM MDT Wednesday for WYZ314>318. High Wind Warning from 4 AM to noon MDT Wednesday for WYZ057-071. High Wind Warning from midnight tonight to 6 PM MDT Wednesday for WYZ054>056. && $$ DISCUSSION...Helgeson AVIATION...Pojorlie FIRE WEATHER...Helgeson