Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 11/24/21

Area Forecast Discussion
National Weather Service Dodge City KS
506 PM CST Tue Nov 23 2021 ...Updated Aviation Discussion... .SHORT TERM...(This evening through Wednesday) Issued at 347 PM CST Tue Nov 23 2021 The water vapor and RAP analysis late this afternoon confirmed quite well the transition of the synoptic pattern from northwest flow aloft yesterday to our current west-southwesterly flow aloft as both a southern stream and northern stream storm system advance east across the western CONUS. Out ahead of the southern stream wave (which was centered just off the southern coast of California), mid and high cloud continued to increase across the Desert Southwest through the Central Rockies and adjacent western Great Plains. This mid and high cloud will become increasingly opaque later tonight and through the day Wednesday. As the two waves approach each other tomorrow across the Central CONUS, the entire mid-tropospheric trough axis will broaden and become increasingly positive-tilted. This trough orientation will favor fairly significant lower tropospheric anticyclogenesis and subsequent high pressure rises at the surface as well as a rapid southward transport of colder air in the low levels. Given the timing of the cold front tomorrow and the strongest cold air advection not really beginning midday or early afternoon, we should still see temperatures warm to close to 60F across much of the forecast areas with lower 60s in the Red Hills region. Afternoon wind speeds will jump to the 20 to 30 mph range out of the north with gusts 40+ mph at times. Fairly strong cold air advection will continue into Wednesday Night/early Thursday morning as 850mb temperatures sink to -2C to 0C by daybreak Thursday. .LONG TERM...(Wednesday night through Tuesday) Issued at 347 PM CST Tue Nov 23 2021 Not much has changed in the overall thinking regarding the Long Term forecast through early next week. Above to well-above normal temperatures will be occurring across our region as the larger hemispheric scale pattern will remain essentially unchanged with a mean trough in the northeastern CONUS and a mean ridge across the western half of the CONUS. After our coolest day Thursday, we will see a rebound in temperatures Friday through early next week. There will be a minor front which will move through Saturday, be impacts on temperature will be negligible late in the weekend. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday evening) Issued at 504 PM CST Tue Nov 23 2021 Gusty southwest winds early this Tuesday evening will decrease to 10 to 15 knots by sunset and then shift to the west during the overnight hours as a surface boundary moves across southwest Kansas. This surface boundary will be quickly followed by a cold front early Wednesday morning. As this cold front passes between 12z and 18z Wednesday the westerly winds at around 10 knots will shift to the north and increase into the 20 to 25 knot range. BUFR soundings indicate an increase in moisture/cloud cover between 09z and 21z Wednesday with cloud bases expected to range from 10000ft to 15000ft AGL. && .FIRE WEATHER... Issued at 347 PM CST Tue Nov 23 2021 Near-critical or Critical fire weather conditions were ongoing as of 330 PM CST across much of our region as south winds were sustained in the 20 to 30 mph range gusting 35-40 mph at times. Relative humidity was in the 14 to 18 percent range east of Hwy 283 and in the 8 to 14 percent range west of Hwy 283. Critical fire weather conditions will lessen by sunset, however winds will still be fairly gusty a few hours after sunset given the strength of the surface pressure gradient. Elevated fire conditions are expected Wednesday afternoon when the north-northeast winds pick up in strength late morning/midday. Expect the same strength in wind speed tomorrow, just out of the opposite direction (North). Since the forecast temperature will be lower, the relative humidity is not expected to reach Critical conditions, so Red Flag Criteria is not expected to be met. It may be close in the far southwest, and the next shift may need to revisit this, however no headlines will be issued this forecast cycle. && .PRELIMINARY POINT TEMPS/POPS... DDC 45 59 25 48 / 0 0 0 0 GCK 41 58 22 49 / 0 0 0 0 EHA 47 58 25 51 / 0 0 10 0 LBL 47 60 25 50 / 0 0 10 0 HYS 42 57 22 46 / 0 0 0 0 P28 49 63 30 48 / 0 0 10 0 && .DDC WATCHES/WARNINGS/ADVISORIES... Red Flag Warning until 6 PM CST /5 PM MST/ this evening for KSZ030-031-043>046-061>066-074>081-084>088. && $$ SHORT TERM...Umscheid LONG TERM...Umscheid AVIATION...Burgert FIRE WEATHER...Umscheid
Area Forecast Discussion
National Weather Service Grand Rapids MI
1030 PM EST Tue Nov 23 2021 LATEST UPDATE... Update .UPDATE... Issued at 1030 PM EST Tue Nov 23 2021 Still not finding any compelling reason to jump into a wind advisory even though latest guidance continues to show 45-50 kts at 925 mb/2000 ft AGL coming into the area tonight and Wednesday. Fcst soundings for Wednesday show a fairly strong inversion below that core of strong winds, which should limit potential for mixing down advisory criteria gusts of 45 mph. Suppose a few brief gusts near advisory criteria could occur, but typically a southerly flow event in late November is not associated with more frequent significant gusts due to poor sun angle and lack of deeper mixing. The immediate Lk MI coastline may stand a better chance, but even at MKG and LDM the ensemble mean wind gusts from the ECMWF are only near 40 mph. On a separate note, have removed PoPs for Wednesday afternoon with latest guidance delaying precip until after 00Z. && .DISCUSSION...(This evening through next Tuesday) Issued at 334 PM EST Tue Nov 23 2021 - Strong south winds develop on Wednesday - We are looking at winds beginning to increase tonight as the gradient tightens. Given it is a night time period, not expecting much vertical mixing and hence just a steady/brisk south to southwest wind. By morning, we should be up around 15 mph which will be noticeable given temperatures in the low to mid 30s. Wind chill values Wednesday morning will be in the low 20s. The main time frame of concern for wind gusts will be during the day on Wednesday. We feel there is potential to see wind gusts up around 40 mph. The HRRR would suggest that we could even flirt with advisory levels in many areas. We think this is slightly overdone, but later shifts will be continually monitoring this threat. We considered issuing a Wind Advisory for Muskegon, Oceana and Mason Counties given a SSW wind off the lake in a mixed boundary layer. We feel there is potential for 45 mph gusts at least in the western portions of those three counties. That said, we did not have consensus for headline issuance with neighboring offices and our confidence is not extremely high either. It will be a windy Wednesday with the highest gusts likely in our northern lakeshore counties. Winds will slacken off with the setting sun tomorrow. - Rain to lake effect snow Wednesday night into Friday - A cold front slides into the area Wednesday night and pushes eastward on Thanksgiving. Rain will break out near the front Wednesday night and continue into Thanksgiving day. The rain will be along and just behind the cold front and will move east of the area Thanksgiving afternoon. Strong cold air advection commences behind the front and we will see lake effect snow across Western Lower Michigan. There will be a burst of lake effect snow Thanksgiving afternoon and evening, probably centered around 700pm. We are likely looking at 1-2 inches of snow during this time frame with the highest likelihood of accumulations across the far northwest CWA up towards Ludington and Baldwin and down in the southwest as well towards South Haven and Bangor. Travel issues do not look to be significant, but we do fall below freezing during the evening, so some slippery travel is possible Thanksgiving evening across Western Lower Michigan. The lake effect should not affect the central and eastern portions of the state much at all. Light lake effect snow will continue into the overnight Thursday night, ending Friday morning. Little in the way of additional snow is expected during this time frame as moisture and lift will both be waining. - Persistent northwest upper flow and mainly dry rest of period - A persistent northwest upper flow is expected from Friday night all the way through next Tuesday. There are some embedded shortwaves that will be moving through the flow with the most notable occurring on Saturday night. Saturday night into Sunday will be a period where we could see a bit of synoptic snow with a surface trough developing, followed by some lake effect into Sunday. Precipitation does not look to be heavy. Overall near normal temperatures and mainly dry conditions through this longer term period. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday evening) Issued at 704 PM EST Tue Nov 23 2021 Strong winds out of the south-southwest will impact aviation interests tonight and Wednesday. VFR conditions will continue through 00Z Wed evening with cloud bases above 10K ft. As the winds increase significantly tonight to 40-45 kts at 1-2K ft by 06Z, but the sfc layer remains stable with winds only around 10-15 kts, expect to encounter low level turbulence/wind shear. After 15Z Wednesday as sfc temperatures warm and deeper mixing commences, those higher winds aloft should occasionally stir downward leading to gusty sfc winds of around 30-35 kts at times. MKG`s close proximity to Lk MI should result in strong gusty sfc winds developing already by 06Z tonight and continuing all day Wednesday. Here the winds will gust as high as 40 kts at times. && .MARINE... Issued at 334 PM EST Tue Nov 23 2021 We have maintained the Gale Warning as is...north of South Haven from 700pm this evening through 700pm Wednesday evening. Gale Warning south of South Haven from 1000am Wednesday to 700pm Wednesday. We have also added a Small Craft Advisory for tonight into Wednesday morning for areas south of South Haven to cover a fairly lengthy period of stronger winds and building waves on the lead end of the Gale down there. Bottom line... we are looking at a rough week on the lake. The Gale looks to peak from late tonight through early afternoon on Wednesday. We look to tap into 40 knots in the mixed layer which is only 1,000 to 2,000 feet deep, but the strongest winds around 50 knots are around the 2,000 foot level. The WaveWatch3 and local wave model runs suggest we will see waves peak in the 10-12 foot range up near Big and Little Sable Points. We are not expecting lakeshore flood issues per the FVCOM water model given along shore flow (out of the south) combined with lower water levels as compared to where we were a year or two ago. Highest water levels on the lake in this event will be found up along U.S. 2 in the Upper Peninsula. We are looking at persistent Small Craft Advisory conditions from Wednesday night through Friday in northwest flow cold air advection. We probably will not see a calm period on the lake until Friday night into Saturday. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...None. LM...Gale Warning until 7 PM EST Wednesday for LMZ845>849. Small Craft Advisory until 10 AM EST Wednesday for LMZ844. Gale Warning from 10 AM to 7 PM EST Wednesday for LMZ844. && $$ UPDATE...Meade DISCUSSION...Duke AVIATION...Meade MARINE...Duke
Area Forecast Discussion
National Weather Service Pendleton OR
658 PM PST Tue Nov 23 2021 .SHORT TERM...Tonight and Wednesday...An upper level trough is exiting the region to the east as a ridge of high pressure builds in from the west. The winter weather advisory for the northern Blue Mountains has been cancelled. Skies will continue to clear overnight with showers over the Cascades and eastern mountains coming to an end around midnight. The ridge will move over the region on Wednesday with some increasing high clouds through the day. Breezy winds this evening will decrease overnight the light winds on Wednesday. Cold temperatures overnight and then back up into the 40s across the Basin Wednesday and 30s in the mountains. && .PREV DISCUSSION... /issued 211 PM PST Tue Nov 23 2021/ SHORT TERM...Tonight through Thursday night...The cold front with the weather system that is currently moving across the region has moved to the east of the Pendleton WFO, and is now over the eastern mountains. The precipitation in the lower elevations have ended and skies are clearing out. In the eastern mountains, snow continues to fall, especially at elevations greater than 4000 feet, where moderate to heavy storm total accumulations are expected. There are also snow showers spilling over the crest of the Cascades on to the higher east slopes. A Winter Weather Advisory continues until 4 PM PST for the OR/WA Cascade east slopes and the crest, and a Winter Weather Advisory for the northern Blue Mountains, including the WA northwest Blue Mountains, until 10 PM this evening. The snow will be enhanced by an upslope west to northwest flow into the eastern mountains through this afternoon and evening. However, in the Cascades, the snow will decrease enough by late afternoon such that significant snow accumulations will no longer be expected after this afternoon. Elsewhere in the forecast area, all precipitation (most of which was a mix of rain, freezing rain, and snow) has ended and temperatures have climbed into the 40s to lower 50s. A drier northwest flow aloft will develop over the region tonight and Wednesday morning ahead of a building upper ridge. The upper ridge axis will be over the forecast area by late Wednesday afternoon. This will be a positively tilted ridge, and there will be moisture riding up and over the top of the ridge, and staying well north of the forecast area Wednesday through most of Thursday. So expect fair and calm weather for Wednesday and most of Thursday. By Thursday evening the ridge will tilt forward until its axis becomes nearly horizontal and then the flow will become zonal over the forecast area. The ridge axis, which will be oriented west-east will shift southward and allow the moisture that is riding over the top of it to sag southward. This moisture will move mostly into the northern and northwest portions of the forecast area late Thursday afternoon or evening and continue into the extended forecast period. However, some of this moisture will slide far enough south to impact the OR/WA cascades and also the northeast mountains of Oregon going into the extended period. Breezy to windy conditions this afternoon over the forecast area will diminish this evening and become mostly light, and then remain light through the rest of the short term forecast period. Beginning Thursday, there will be a substantial warming trend, with high temperatures in the lower elevations rising into the 50s by Thursday afternoon, and even higher during the extended period. There are no significant EFI indexes from the ECMWF ensembles over the forecast area in the short term period, and the short range ensembles, such as the HREF, SREF, and HRRR are in good agreement with the deterministic models a far as the flow pattern and precipitation distribution goes. Therefore, there is high confidence in the forecast. 88 LONG TERM...Friday through Tuesday...Model ensembles and model clusters are in good agreement through the long term period in having a ridge over our area. We will be on the northern extent of the ridge as the central high pressure moves from off the southern California coast on Friday to the desert southwest by Monday and Tuesday. Generally fair and warmer conditions are expected though weak shortwaves will ride over the ridge occasionally. One will move through the area Friday with light rain mainly in the mountains tapering off in the afternoon and evening. Snow levels will be around 7500 feet with this wave. Another even weaker wave passing further north will bring more light showers mainly to the Cascades Saturday. Snow levels will be up to 8500 feet so rain is expected but will be barely measurable away from the Cascade crest. As the flow turns southwest, Sunday and Monday will have a slight chance of rain showers along the Cascade crest and dry elsewhere. Models bring a stronger wave through the area either Monday night or Tuesday though once again the main precipitation will be along the Cascades. Warm temperatures are expected through the period with the ECMWF ENS Percentiles and the NAEFS Percentiles both showing temperatures in the 90th percentile or higher Friday through Tuesday with it peaking on Sunday. High temperatures are forecast to be in the 50s with mid 40s to lower 50s in the mountains. Lows will be in the upper 30s to mid 40s with mainly 30s in the mountains. However, past experience would indicate that a ridge over the area and generally light winds would be favorable for low stratus and fog. If that does occur, then the Columbia Basin and adjacent valleys would likely have high temperatures in the 30s, similar to the last couple of days. This will be something later forecasts will have to watch. Perry/83 AVIATION...00Z TAFS...Skies are clearing though FEW-SCT low clouds remain at a few sites, including SCT006 at YKM. Expect that these will dissipate in the next few hours. Skies will become clear aside from high cirrus tonight and tomorrow morning then will begin increasing above 10K feet AGL after 18Z in advance of an approaching shortwave. Winds will continue at 10 to 20 kts with gusts to 30-35 kts through about 02Z then begin decreasing. Winds will drop below 12 kts at all TAF sites by 08Z and remain there through 00Z tomorrow afternoon. Perry/83 && .PRELIMINARY POINT TEMPS/POPS... PDT 28 47 30 53 / 10 0 0 0 ALW 33 47 33 52 / 10 0 0 10 PSC 32 48 34 50 / 0 0 0 10 YKM 25 44 30 48 / 0 0 10 20 HRI 31 48 33 50 / 10 0 0 0 ELN 28 44 30 47 / 0 0 10 30 RDM 23 49 30 57 / 0 0 0 0 LGD 25 43 29 45 / 20 0 0 0 GCD 25 44 28 53 / 20 0 0 0 DLS 34 49 37 54 / 10 0 0 20 && .PDT WATCHES/WARNINGS/ADVISORIES... OR...None. WA...None. && $$ SHORT TERM...91 LONG TERM....75 AVIATION...75