Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 10/11/22

Area Forecast Discussion
National Weather Service Billings MT
646 PM MDT Mon Oct 10 2022 .UPDATE... Satellite imagery shows a shortwave dropping thru Alberta, which is our next weather-maker for tomorrow. A cold front is not quite to Calgary, and this front will reach southeast MT late tonight. There is even some lightning along the trof axis upstream in AB/BC. Today was a pre-frontal warm day and breezy west winds will continue along the foothills tonight until the front arrives. Latest models suggest the chance of showers will arrive in our northwest beginning around 09z, then shift quickly to the S/SE through the morning, becoming enhanced for a short time along our southern upslope areas. For Billings, 12-15z looks like the main time period for showers. Given what is happening to our north, and model forecasts of a little elevated cape along the cold front, cannot completely rule out a few lightning strikes early tomorrow. Forecast is in good shape, but did adjust pre- and post-frontal winds up a bit, and tapered off pops/wx in our north tomorrow after 15z. JKL && .DISCUSSION... Today through Wednesday night... Two main concerns for the forecast this period. Timing of showers moving in with a cold front tonight/Tuesday, and wind speeds Tue./Wednesday. Cold front was seen over S. Central Alberta late this morning in surface obs and on satellite imagery. SREF showed the front moving through the area late tonight through Tue. morning. Front will be driven by a strong jet on the W side of an upper trough. Left-exit region of this jet pushes out of the area around 00Z Wednesday as lift from the trough pushes to the E. SREF brought precipitation into the area between 12Z and 15Z, while deterministics brought it in after 09Z. Meanwhile, CAMS had a more aggressive southward push of the precipitation overnight. Noted CAMS were picking up on some echoes in the Pacific NW, but these were just mid clouds. Therefore, kept precip. timing closer to SREF and deterministic models. Future shifts can watch the timing of the showers this evening. So this will be a quick shot of precipitation, moving into the NW after 09Z and moving S of the forecast area by around 21Z. Snow levels drop to around 7000 ft which will keep snow out of the foothills like Red Lodge. QPF amounts were a couple tenths of an inch at most, so mountains could have an inch or two of snow. HRRR reflectivity was suggestive of some thunder with the showers on Tue., but soundings did not support thunder. For winds, meteograms suggested mean gusts in the 30s over parts of the area on Tuesday and it will also be breezy tonight with the frontal passage. Thus, nudged winds toward the NBM 90th percentile. Tuesday night through Wednesday night will feature fast NNW flow aloft, with the NAEFS showing around 50 kt in the E at 700 mb and 30-40 kt at 850 mb. The EFI had a .8 for winds which showed climatologically above normal wind speeds and a SOT of 0 for the wind gusts in the E. Meteograms had winds gusting into the 40s over the E. Pushed winds up to the NBM 90th percentile Tue. evening and on Wednesday. There was a weak vorticity push with some 850-700 mb frontogenesis late Tue. night into early Wed., but time-heights did not show moisture reaching the ground, and NBM was dry along with the SREF. Thus left these periods dry for now. Temperatures will be near normal, which was in the lower 60s, for both days. Arthur Thursday through Monday... Northwest flow dominated the weather pattern going into the weekend before the upper ridge axis eventually shifts east early next week. This unsettled flow will keep temperatures near-normal for much of the period, winds relatively light, and fairly dry. However, a small number of ensemble members do indicate a weak shortwave occurring Saturday into Sunday morning which would bring widespread rain to the area and overcast conditions. With only a small number depicting this so far, only a very small chance exists of this occurring, and isn`t represented in the deterministic forecast so far. Signs of a brief warm-up occur early next week when the ridge shifts over us. Vertz && .AVIATION... Breezy winds will persist at KLVM through the night. Frontal passage will swing through all terminals Tuesday morning, bringing with it showers in the vicinity of all terminals and a shift to northwest winds which will see peak speeds by the late morning to early afternoon. Vertz && .PRELIMINARY POINT TEMP/POPS... Tue Wed Thu Fri Sat Sun Mon ----------------------------------------------------------- BIL 049/060 042/060 039/067 044/072 046/064 039/063 039/067 26/W 00/U 00/U 00/U 12/W 10/U 00/U LVM 044/063 038/066 036/071 040/072 040/066 036/069 038/072 25/W 00/U 00/U 00/U 11/B 10/U 00/U HDN 046/061 039/060 035/066 039/074 043/066 036/064 035/069 16/W 00/B 00/U 00/U 12/W 10/U 00/U MLS 049/059 042/058 036/061 039/069 045/061 036/058 035/064 03/W 10/N 00/U 00/B 11/B 10/U 00/U 4BQ 047/057 041/056 037/059 040/069 044/061 036/058 035/065 04/W 10/N 00/U 00/U 02/W 10/U 00/U BHK 048/057 039/055 034/057 037/067 043/058 031/054 031/059 04/W 10/N 00/U 00/B 02/W 10/U 00/U SHR 047/058 037/059 036/064 039/072 043/064 036/063 037/069 07/W 00/U 00/U 00/U 12/W 10/U 00/U && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...None. WY...None. && $$
Area Forecast Discussion
National Weather Service Columbia SC
807 PM EDT Mon Oct 10 2022 .SYNOPSIS... Temperatures moderate through midweek. There is a high chance (40% to 60%) of rain late Wednesday into Thursday as a cold front moves through the Southeast. A dry, cool airmass will follow for late this week and the weekend. && .NEAR TERM /THROUGH TUESDAY/... Things are fairly quiet across the FA this evening. Strato-cumulus had diminished a bit, especially across the western Midlands and CSRA, but it is beginning to come back again. Persistent southeasterly flow at 925 hPa and isentropic ascent between the 290K and 300K theta surfaces is maintaining the cloud cover. This actually beginning to expand westward again and should continue to do so over the coming hours. The HRRR has a good handle on this again, and leaned towards that in my grid update. Temperatures are likely to be fairly warm again tonight as we get blanketed by strato- cumulus. The CSRA is the place most likely to cool over the coming hours, but the central and eastern Midlands are likely to only see lows fall into the upper 50s and low 60s again overnight. Precipitation is unlikely, as there aren`t any shortwaves to augment the isentropic ascent, and moisture is fairly shallow. Most places have PWs at or below 1", but I can`t rule out an isolated shower or two overnight. Surface northeasterly flow will remain light, but should be persistently northeasterly as we are in a semi-weak wedge like set up. && .SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY NIGHT/... Surface high pressure to the northeast will shift further offshore Tuesday and Wednesday as an upper trough digs into the central US. This will allow moisture to creep back into the forecast area on Tuesday. Expect overcast or mostly cloudy skies across the CSRA by daybreak then, spreading northward and into the remaining portions of the forecast area during the day. Although PWAT values are increasing, moisture will remain shallow through Tuesday evening and no rainfall is expected. CAMs add confidence keeping and measurable precip west of the FA through that time. The upper trough will continue to dig into the eastern US on Wednesday and Thursday. The associated cold front will push into the Southeast on Wednesday and push east of the forecast area on Thursday. Global models have shown some run-to-run inconsistencies in recent runs making it difficult to nail down the exact timing of the frontal passage and associated rainfall. However as moisture begins to deepen on Wednesday morning light scattered showers will becoming increasingly likely as isentropic lift strengthens. The deepest moisture and heaviest showers should occur between Wednesday afternoon and Thursday morning ahead of the cold front. The strength of the warm, moist advection varies between models with the NAM being one of the more aggressive models. Weak surface based instability could support thunderstorm development in the moderately sheared environment. Although severe weather potential appears low it will need to be monitored through the week. Thursday, the cold front and deepest moisture will edge away from the FA leading to decreasing rain chances and clearing skies. There could be some lingering showers as the front moves through on Thursday but without the presence of the deeper moisture we expect rain amounts to be light. Dry, cool air continues to enter the region overnight. && .LONG TERM /FRIDAY THROUGH MONDAY/... Dry, high pressure will move into the Southeast late this week providing seasonable temperatures and clear or mostly clear skies through the end of the long term. High temperatures will generally be in the 70s, with lows in the 40s all except Sunday night. The most favorable radiational cooling night appears to be Saturday night. This favors low temperatures a few degrees cooler than the National Blend of Models suggests. If models continue to show surface high pressure centered over the region, clear skies and light winds then temperatures may need to be dropped even more than currently forecast. && .AVIATION /00Z TUESDAY THROUGH SATURDAY/... Periods of VFR this evening, though CIGS expected to lower to MVFR restrictions late tonight into early Tuesday. SFC winds NELY 5 to 10 knots. Mainly VFR conditions by 11/15z Tuesday morning, though SCT- BKN clouds 4-6kft MSL expected much of the day. Winds continue ELY/SELY 5-10 kts into Tuesday afternoon. EXTENDED AVIATION OUTLOOK...Restrictions possible by late Wednesday and early Thursday as a cold front moves through the area. No significant impacts to aviation expected behind the front Thursday afternoon through Saturday. && .CAE WATCHES/WARNINGS/ADVISORIES... GA...None. SC...None. && $$ SYNOPSIS... NEAR TERM... SHORT TERM... LONG TERM... AVIATION...
Area Forecast Discussion
National Weather Service Wichita KS
604 PM CDT Mon Oct 10 2022 .SHORT TERM...(This evening through Thursday night) Issued at 222 PM CDT Mon Oct 10 2022 Weak southwest surface flow will lead to warm advection and 850-700h moisture transport increasing across northern Oklahoma into southern KS and the Flint Hills this evening and especially after midnight. This will lead to a gradual increase in the chance for showers and a few storms for areas mainly east of the KS Turnpike this evening and overnight. Areas east of the Flint Hills have the best chance of seeing better areal coverage and rainfall amounts, with rainfall amounts possibly of a half to three quarters of an inch expected. Minimal instability and weak shear will probably preclude anything strong or severe, but a few rumbles of thunder may occur over SE KS either late tonight or early Tue. By tue morning, Latest RAP shows most of the moisture transport veers out to the east, into the Ozarks. So think most of the showers and embedded storms will shift east of the area by early on Tue. A more pronounced upper trough will be digging across the Northern Rockies into the Northern High Plains during the day on Tue. Ahead of this wave, we will see above normal temperatures, given good downslope SW flow, with gusty southwest winds, especially for areas east of the KS Turnpike. The combination of the gusty winds, dry antecedent conditions will lead to elevated fire weather conditions for Tue. (See fire weather section below). Expect well above normal temperatures again on Tue, given the good downslope flow, with afternoon highs generally in the low to middle 80s. Normal highs for this time of year are in the low to mid 70s. A northern Rockies shortwave will push a strong cold front SE into the forecast area for Tue evening and Tue night. Increasing convergence along the front, will lead to an increase in showers and thunderstorms across central KS for Tue night, as the main shortwave swings south across northern sections of the forecast area. Think the best shower/storm coverage will be across central KS and areas north of a KSLN to KCNU line. Decent mid level lapse rates and bulk shear values of 35 to 40 kts, may lead to some strong to marginally severe storms with nickel to quarter size hail the main concern, given elevated instability around 1000 J/KG. The strong cold front quickly pushes east of the area by Wed morning, with some lingering showers/storms expected over extreme SE KS for early Wed morning. Otherwise, expect breezy NW winds behind the front with dry conditions. A large upper level trough develops over the Great Lakes region for the middle of the week, which will keep the forecast area in NW flow for most of the week. Even with the NW flow aloft, expect seasonal temperatures for both Wed and Thu, as most locations see favorable downslope flow with sunny skies. Ketcham .LONG TERM...(Friday through Monday) Issued at 222 PM CDT Mon Oct 10 2022 Some model differences on how the end of the week will play out, with the GFS showing a baroclinic zone setting over southern KS for late Sat, ahead of a another cold front. Which may lead to a small shower chance. But the ECMWF keeps things dry. Expect a gradual warming trend going into the weekend. Ketcham && .AVIATION...(For the 00Z TAFS through 00Z Tuesday evening) Issued at 601 PM CDT Mon Oct 10 2022 Scattered rain showers will affect parts of south central Kansas during the evening hours. This activity will diminish around 02Z then expect another round to develop over Oklahoma later tonight and spread northeastward into Southeast Kansas. Meanwhile low clouds in the MVFR range will be possible across southern Kansas during the early morning hours on Tuesday. South winds will be on increase during the daytime hours Tuesday. Storms look to re- develop across southern Kansas during the afternoon hours on Tuesday. && .FIRE WEATHER... Issued at 222 PM CDT Mon Oct 10 2022 An Elevated fire risk will be in place for Tuesday and then again for Thursday and Friday. For Tuesday, strong southwest winds to be in place, especially across the Flint Hills into southeast Kansas. Expect sustained winds of 25-30 mph with gusts 35 to 40 mph. At the same time, afternoon relative humidity values will be around 40% on Tue, with values around 30% over central KS. This will lead to widespread very high grassland fire danger with extreme values possible for areas east of the Kansas Turnpike, where winds be will stronger. A very dry airmass will overspread the region for both Thursday and Friday with some gusty winds possible. So confidence is high that very high grassland fire danger will also be in place for both days. && .PRELIMINARY POINT TEMPS/POPS... Wichita-KICT 61 84 57 74 / 30 10 30 0 Hutchinson 59 84 53 74 / 20 10 30 0 Newton 61 83 55 73 / 30 10 40 0 ElDorado 61 82 57 73 / 40 10 40 10 Winfield-KWLD 61 83 58 75 / 40 10 40 0 Russell 58 86 49 74 / 10 0 20 0 Great Bend 57 84 49 74 / 10 0 20 0 Salina 61 86 52 74 / 10 0 40 0 McPherson 59 84 53 73 / 20 10 40 0 Coffeyville 62 82 61 77 / 60 20 50 20 Chanute 62 82 59 74 / 50 20 60 20 Iola 61 82 58 74 / 50 20 60 20 Parsons-KPPF 63 82 61 76 / 50 20 50 20 && .ICT WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...Ketcham LONG TERM...Ketcham AVIATION...CDJ FIRE WEATHER...Ketcham
Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
1048 PM CDT Mon Oct 10 2022 .UPDATE... Issued at 930 PM CDT Mon Oct 10 2022 Forecast is on track for showers and a few thunderstorms to move into the area overnight into Tuesday. 00Z upper air analysis is showing 8-10C 850mb dewpoints at SGF and OUN that will be advecting northeastward as the RAP is showing a low level jet increasing to 40+ knots after 06Z. Latest regional radar is showing that scattered showers are already moving northeast across southwest Missouri into northeast Oklahoma and expect showers to expand across the CWA after 06Z as moisture convergence with the low level jet increases ahead of a shortwave over the Central Plains. This is depicted well on the latest runs of the CAMS. Latest objective analysis is showing about 500 J/kg of MUCAPE which persists through the night, so will continue with the chance of thunderstorms. Britt && .SHORT TERM... (Through Late Tuesday Afternoon) Issued at 249 PM CDT Mon Oct 10 2022 The more active pattern we have been discussing is still on track to get underway tonight with our first decent rain for much of the area set to begin overnight and continue into Tuesday. The overall scenario hasn`t changed, however the axis of the highest rainfall probabilities and rainfall amounts has shifted slightly south from this time 24 hours ago and the northeastward spread is more accelerated. The short wave trof currently located across the high Plains will move eastward tonight with a series of weak vort maxes in the southwest flow aloft in advance of it tracking into the area. While weak large scale ascent is expected with these features, the main driver will be a 40+ kt southwesterly LLJ that will provide good moisture transport/convergence/thetae advection and that will be augmented by divergence aloft in the entrance region of an ULJ to our east. The SREF is still indicating a 50-90% probability of MUCAPE of 250+ J/KG generally along and just north of I-44 and the HREF is in that range as well, thus supportive of at least isolated embedded thunderstorms. Current thinking is showers and a few thunderstorms will develop through central MO between 06-09z and spread quickly to the northeast, overspreading southwest and south-central IL between 11-14z. The precipitation should exit the area in the afternoon in association with migrating of the lead shortwave and aforementioned vort maxes. Clouds and precipitation will make for a much cooler day with the areas along the fringe of the rain shield, northeast MO and southeast MO seeing the warmest temps. Precipitation with this round while beneficial won`t be anything exceptional with the majority of the exceedance guidance indicating amounts in the 0.25-0.75 inch range and the HREF LPPM suggesting some isolated amount of 1+ inches. Glass .LONG TERM... (Tuesday Night through Next Monday) Issued at 249 PM CDT Mon Oct 10 2022 The precipitation trends on Tuesday evening remain a bit unclear and whether there will be additional vort maxes aiding in generating any showers and storms in the wake of the earlier activity during the evening hours given the presence of a southwesterly LLJ. I think the higher probability scenario is an uptick in showers and storms overnight, especially in the 08-12z time frame and especially across the northwest third of the CWA along and ahead of the advancing cold front and in association with robust large scale forcing with the sharp digging upper trof. The cold front will track rather quickly southeastward through the CWA on Wednesday in response to the digging trof and should be accompanied by scattered to numerous showers and some storms. As far as the severe threat - we are not currently messaging the threat at this time which looks highly conditional. The SPC DY2 would be in the 08-12z Wednesday time frame across the northwest CWA. Only the NAM has much in the way of CAPE, with the SREF and HREF showing values generally in the 250-500 J/KG range. While there will be good forcing I think the most likely scenario barring more instability is gusty winds with any storms or an outflow boundary. The SPC DY3 is also highly dependent on instability. While deep layer shear is pretty good, the instability once again along/ahead of the front is in question and the bulk of the guidance supports CAPE values generally in the 250-500 J/KG range (lesser on the SREF) across parts of southeast MO and southern IL in the afternoon. Rainfall on Wednesday should generally be less than Tuesday, mostly likely in the 0.10-0.50 inch range. An anomalously deep longwave trof will be anchored over eastern NOAM during the later part of the week bringing several days of cooler weather. Variance in the details of the eastern longwave trof Saturday-Sunday and short waves rotating through it lead to lower than normal confidence in some details of the forecast. It does look like we should see a warm-up on Saturday ahead of a cold front that will move through late Saturday-Saturday night. The front could be accompanied by scattered showers and should lead to cooler temps on Sunday but there is a good spread in the NBM on how cool. There are indications the longwave will reload on Monday, deepening and bringing even cooler air. Glass && .AVIATION... (For the 06z TAFs through 06z Tuesday Night) Issued at 1040 PM CDT Mon Oct 10 2022 Showers over southwest Missouri will expand and move northeast reaching COU/JEF around 09-10Z and UIN and the St. Louis metro terminals between 11-13Z. The rain will initially start out with VFR ceilings and visibilities but then drop to 3-5 mile visibilities during the morning. Ceilings are expected to drop into the low VFR range, though MVFR ceilings are possible. The rain will begin to diminish from southwest to northeast during the afternoon and will end by evening. There is a low chance for thunderstorms with this system, but confidence is too low to include in the TAFs at this time. Winds will remain out of the south to southeast through the period and will gust into 20-25 knot range at times during the afternoon and evening. Britt && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && $$ WFO LSX
Area Forecast Discussion
National Weather Service Medford OR
249 PM PDT Mon Oct 10 2022 .DISCUSSION... A lot of lingering haze and smoke is still spread out over southern Oregon and northern California this afternoon. Satellite data shows fresh smoke from the Cedar Creek Fire spreading towards the south east under lighter northerly flow. That smoke should settle over sections of Klamath and Lake counties later this evening reducing the air quality in the valleys. A dry cold front will move through the forecast area later this evening into Tuesday morning. Cloud coverage should increase a bit in addition to the atmosphere becoming more mixed behind the front. This should result in some of the smoke and haze clearing out here west of the Cascades. However, conditions are not expected to improve much east of the Cascades according to the HRRR Smoke model. As the front moves through tonight, moisture should push farther inland with low clouds covering the Umpqua Basin and the coastal valleys. Some light drizzle over higher terrain and the coastal range is within the realms of possibility. With relatively cooler air moving in, high temperatures will trend about 5 to 10 degrees cooler across the region. Perhaps because of the cool down, the HRRR Smoke model tapers down fire activity over the Cedar Creek Fire on Tuesday. Given current fire activity,dry conditions and current fire containment, we suspect the model is under doing smoke output on Tuesday. Other than the persistent smoke issues, no big weather hazards are on the horizon as high pressure will build in quickly Tuesday into Wednesday. We`ll see temperatures warm back up to 10 to 15 degrees warmer than normal for most locations. To really emphasize this point, we`re forecasting a high of 90 degrees in Medford on the 15th of October at this time. If this did occur, it would be the 2nd latest 90 degree day on record for Medford. The record is 92 set in 10/15/2015. The ridge will eventually break down sometime around the 17th to 18th as a low approaches the Oregon coast. The NBM is also putting a 15% chance of precipitation in the forecast around the 17th and 18th as well. This period of time should become more clear over the next few days. -Smith && .AVIATION...10/18Z TAFs...Over the coastal waters, along the coast, and in the coastal valleys...Widespread IFR/LIFR cigs/vsbys in low clouds and fog will clear to the coast Monday afternoon, but will persist through Monday over the coastal waters and portions of the coast. The lower conditions will return to the rest of the coast Monday evening, spreading into the coastal valleys Monday night. The lower conditions will then persist into Tuesday morning. In the Umpqua Basin...Areas of IFR cigs/vsbys will return late Sunday night, clearing to VFR by Monday afternoon, except for some MVFR vsbys in haze and smoke. The lower conditions will return late Monday night, persisting into Tuesday morning. Over the remainder of the area...VFR conditions will persist into Tuesday morning, except for some MVFR vsbys in haze and smoke. && .MARINE...Updated 100 PM Monday 10 October 2022...A thermal trough near the coast will strengthen Monday and weaken Wednesday. This will bring a period of gusty north winds and steep to very steep seas to the waters. Winds and seas will be highest south of Cape Blanco, peaking in the afternoons and evenings. The thermal trough will redevelop Thursday night, and gusty north winds and steep seas will return to the area Thursday night through Saturday. && .FIRE WEATHER...Updated 200 PM PDT Oct. 10, 2022...During the period of brief east flow from tonight through Tuesday night, dry air will enter the region. This will lead to stunted recoveries along mid- slopes and ridges, and to some degree valleys too. Winds will be strongest across the higher terrain with gusts of 15 to 20 mph common, and up to 25 to 30 mph across the coastal mountains of Curry County. Easterly flow strengthens Tuesday night. Gusts of 15 to 20 mph will be common, though the strongest speeds (up to 25 to 30 mph) are expected along the Cascades Tuesday night. Brief and isolated instances of critical conditions are possible Tuesday night in eastern FWZ 617 and more isolated in central 621. On Wednesday, conditions return to those experienced last week, with cool mornings and very light east flow across higher terrain at night, and warming temperatures in the afternoons with northerly winds. Recoveries are likely to remain moderate through Friday, before valleys and mid- slopes see more substantial recoveries during the weekend. && .MFR WATCHES/WARNINGS/ADVISORIES... OR...CA...None. Pacific Coastal Waters...Small Craft Advisory until 11 AM PDT Wednesday for PZZ350-356- 370-376. Hazardous Seas Warning until 11 AM PDT Wednesday for PZZ356-376. && $$