Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 08/17/22

Area Forecast Discussion
National Weather Service Dodge City KS
1100 PM CDT Tue Aug 16 2022 ...updated aviation... .SHORT TERM...(This evening through Wednesday) Issued at 1257 PM CDT Tue Aug 16 2022 Main challenge tonight will be precipitation chances and potential for heavy rainfall from storms moving across portions of extreme southwest Kansas. CAMS are coming into better agreement today with a moist upslope flow developing this Tuesday afternoon across southeast Colorado and the Panhandle of Oklahoma. This moist upslope flow combined with afternoon heating will likely result in scattered afternoon convection across southeast Colorado. These thunderstorms will then track southeast along this moist instability axis overnight and 700mb 10-12C temperature gradient which would place locations near and southwest of a Lakin to Meade line in a favorable area (30-80%) for overnight thunderstorms. Highest/most favorable area will be Morton county (80%). Thunderstorms that do cross this area overnight will be capable of producing heavy rainfall based on the RAP forecast of precipitable water values in this area ranging from 1.4 to 1.6in and 12z Tuesday HREF has a +70% probability of >=1” 6hr rainfall appearing across Morton county from 00z to 06z Wednesday. Later shifts will monitor the flash flood potential but at this time given the high 1, 3, 6hr flash flood guidance tonight and how isolated the heavy rainfall is expected have decided not to issue a Flash Flood Watch for tonight for extreme southwest Kansas. Isolated wind gusts of 50 to near 60mph will also be possible early in the event, before sunset. This cluster of thunderstorms will continue to track across the Panhandle of Oklahoma/Texas Panhandle and into western Oklahoma early Wednesday. Any lingering precipitation, mainly near the Oklahoma border is expected to taper off after 18z Wednesday as an upper level trough moves across western Kansas. Temperatures will be unseasonably cool with highs ranging from the upper 70s to lower 80s. .LONG TERM...(Wednesday night through Tuesday) Issued at 1257 PM CDT Tue Aug 16 2022 The key message in the later periods are the extended cooler, more seasonal, temperatures. Will also be monitoring the potential for some widespread rain returning to portions of southwest Kansas. The latest ECMWF and GEFS ensembles remain in generally good agreement through the end of the week with the largest discrepancy over the weekend being the strength and exact location of an upper low that will be moving out of south central Canada and into the western Great Lakes. A cold front will be working its way south across the Northern Plains but at this time it appears that this front and cooler air now will be ending up staying north southwest Kansas. This further north cold front position solution does support not introducing a cooling trend this upcoming weekend..HOWEVER given that both the ECMWF and GEFS ensembles both are showing that a 500mb deformation zone along with a increasing moisture and lift over some part of southwest Kansas which would not only favor increasing chance for precipitation but will also result in cooler temperatures. Confidence at this time is not high that far out in the forecast period on exactly where this moisture, lift and cooler temperatures will be located so stay close to the latest guidance for a chance for precipitation or high temperatures from Sunday through early next week. Given all this it appears southwest Kansas will enjoy highs in the 80s through Friday with upper 80s to lower 90s being possible until the clouds and precipitation returns due to the developing deformation zone. The coolest temperatures late this weekend into early next week along with improving chances for precipitation will occur west and south of Dodge City. In this area highs only in the 70s look to be a real possibility if everything comes together. && .AVIATION...(For the 06Z TAFS through 06Z Wednesday night) Issued at 1111 PM CDT Tue Aug 16 2022 A weather system will impact the terminals through the overnight hours. Showers with isolated thunder will continue across far SW Kansas, with the main impacts at KLBL through the early morning. In addition, upslope stratus will continue to fill in across the terminals through the next several hours. MVFR/IFR cigs will be likely during this period. There could be some patchy fog/br across central Kansas where the moisture is more confined to the near sfc. Winds will remain NE 5-15 kt through much of pd. && .PRELIMINARY POINT TEMPS/POPS... DDC 61 79 58 88 / 30 20 0 10 GCK 61 80 57 87 / 50 10 0 10 EHA 61 76 58 86 / 70 60 0 20 LBL 63 78 59 87 / 70 60 0 10 HYS 62 81 57 88 / 10 10 0 0 P28 65 80 60 87 / 30 20 0 0 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Burgert LONG TERM...Burgert AVIATION...Sugden
Area Forecast Discussion
National Weather Service Pendleton OR
840 PM PDT Tue Aug 16 2022 .UPDATE...High pressure is forecast to dominate the areas weather with dry conditions and hot temperatures for the remainder of the week. Afternoon high temperatures across the Columbia Basin are expected to climb toward 100 degrees and higher and a heat advisory remains in effect for a large part of the region into Friday. Meanwhile high pressure just to our east will remain nearly stationary and some moisture may rap around and into portions of central Oregon tomorrow afternoon that could produce an isolated thunderstorm. Otherwise minor changes were done to sky and overnight temperatures tonight and the present short term forecast appears on track. && .PREV DISCUSSION... /issued 445 PM PDT Tue Aug 16 2022/ SHORT TERM...The main challenges with the short-term forecast revolve around a couple shortwaves anticipated to ride around the upper-level ridge on Wednesday and Thursday. The first of these waves is currently visible off the northern California coast on water vapor imagery. Monsoonal moisture transport up the back side of the ridge will reach central Oregon and the Cascade crest Wednesday morning and afternoon. This moisture, combined with some weak synoptic lift from the shortwaves may facilitate elevated showers and isolated thunderstorms for the central Oregon Cascades, central Oregon, and Ochocos Wednesday afternoon. Overnight into Thursday, guidance advertises another vorticity maximum moving onshore and forming a weak mid-level low. The current track is forecast to move southwest to northeast across eastern Oregon or northern Nevada, though guidance is still struggling with this feature. Thus, while additional lift will be provided by the low, confidence in exact placement of showers and isolated thunderstorms is low for Thursday afternoon into Thursday night. The majority of the moisture is anticipated to push along the Cascade crest Thursday, with perhaps some spilling into the rest of eastern Oregon Thursday evening and night. Have a slight chance of thunderstorms forecast for the Cascade crest on Thursday, as this is where the best instability and moisture is expected. The other concern for Wednesday and Thursday will be very hot temperatures for much of our CWA. Widespread highs in the 95-105 range are forecast Wednesday, and multiple Heat Advisories will be in effect Wednesday morning through Friday evening. Thursday, more uncertainty surrounds afternoon temperatures with potential mid- level cloud cover due to the monsoonal moisture and potential convective debris from any activity on Wednesday. Highs in the 95-105 range are still forecast, but these may come down a few degrees should cloud cover inhibit daytime heating. Regardless, advisory level heat will likely continue through the short term. Plunkett/86 LONG TERM...Friday through Tuesday...Upper ridge will continue to weaken as an upper trough off the coast tries to move into the region. The forecast area will be in the saddle between the upper ridge to the east and the upper trough off the coast to the northwest, and another upper ridge to the southwest along the CA coast. There will be some weak instability, but very little moisture, so Friday looks to be dry. However, cannot rule out an isolated weak thunderstorm over Wallowa County, but the chances are very small, with low confidence. Temperatures still look to be in the upper 90s to lower 100s in the lower elevations and mostly 80s to lower 90s mountains on Friday. Friday night and Saturday, the upper trough off the coast and the upper ridge over Montana will cause a southwest to west flow over the forecast area. There will also be a subtle upper low over the great basin, but that will have no effect on the weather in the CWA. Therefore, at this time, it looks to remain dry through Saturday night into early Sunday. However, the upper trough off the coast is now forecast by both the ECMWF and GFS to move into the region and forecast area by Sunday afternoon. This will result in a slight chance of thunderstorms over mainly the Elkhorn and Wallowa Mountains. However, elsewhere it will stay dry. A slight chance of thunderstorms will persist Sunday evening, and then dissipate overnight. There may still be a few showers, mainly over Wallowa County and the northern Blue Mountains Sunday night and Monday morning. Then with afternoon heating on Monday, combined with the upper trough that will still be moving across the region, there will be another slight chance of thunderstorms over Wallowa County. Then on Tuesday, a drier northwest flow will develop behind the trough as it departs the region. Tuesday looks to be dry. Temperatures on Monday and Tuesday will be cooler, with highs in the 90s in the lower elevations, and mid 70s to mid 80s mountains. While these temperatures are still above normal, it will feel cooler compared to the triple digit heat in the short term and in the early long term forecast period. It will be breezy to windy in the eastern Columbia River Gorge/north central OR area, as well as possibly the Kittitas Valley Friday afternoon and evening. After that winds look to be mostly light, except for the usual locations where winds tend to increase during the afternoons and evenings, such as the eastern Columbia Gorge and Kittitas Valleys. AVIATION...vfr conditions are expected to continue for the next 24 hours. Winds are forecast to remain between 5 to 20 mph. Meanwhile taf sites krdm and kbdn may experience few-sct100 after 20z. && .PRELIMINARY POINT TEMPS/POPS... PDT 61 101 65 99 / 0 0 0 0 ALW 63 104 67 102 / 0 0 0 0 PSC 64 104 68 103 / 0 0 0 0 YKM 60 101 67 103 / 0 0 0 0 HRI 62 105 67 103 / 0 0 0 0 ELN 60 102 66 103 / 0 0 0 0 RDM 56 99 64 95 / 0 20 20 10 LGD 59 100 62 96 / 0 0 0 0 GCD 59 104 64 97 / 0 0 0 0 DLS 67 105 75 103 / 0 0 0 10 && .PDT WATCHES/WARNINGS/ADVISORIES... OR...Heat Advisory from 11 AM Wednesday to 11 PM PDT Friday for ORZ041-044-049-050-502-503-505>508-510-511. WA...Heat Advisory from 11 AM Wednesday to 11 PM PDT Friday for WAZ024-026>030-520-521. && $$ SHORT TERM...97 LONG TERM....99 AVIATION...97
Area Forecast Discussion
National Weather Service Las Vegas NV
830 PM PDT Tue Aug 16 2022 .SYNOPSIS...Scattered showers and thunderstorms will persist through the week as monsoonal moisture remains over the region, and any storms will be capable of producing locally heavy rain and flooding. With the abundant moisture in place, temperatures will remain near to slightly below normal into the weekend. && .UPDATE...A few thunderstorms were persisting after sunset and moving from southwest Lincoln County into the area around Indian Springs and Mercury early this evening...similar to convective development that occurred Monday evening. The 00Z Las Vegas sounding and the most recent mesoanalysis indicate the environment is more stable than 24 hours ago with mixed layer cape values around 100-200 J/kg and most unstable CAPE values around 200-400 J/kg. The northeast steering flow aloft should direct any additional development toward the Pahrump Valley. The latest HRRR indicates this trend, but can`t completely rule out some showers or thunderstorms brushing the northern portion of the Spring Mountains and far northwest parts of the Las Vegas Valley through late evening. -Adair && .PREV DISCUSSION... 1227 PM PDT Tue Aug 16 2022 .SHORT TERM...through Wednesday night. Late morning satellite loop showed shallow cumulus bubbling over much of the CWA, with deeper convection beginning over the Hualapai Mountains and in southern Esmeralda County. Surface obs showed temperatures running a few degrees warmer than 24 hours ago, although still well below mid August averages, and dewpoints a few degrees lower than yesterday. With the deep moisture and some instability in place, no spot can be completely ruled out for thunderstorm chances this afternoon and evening, although the high resolution models are in decent agreement that the lowest chances will be in the Death Valley region and the lower elevations of Clark County. Models show a bit less instability Wednesday, resulting in a bit less thunderstorm coverage as well. However, this could be modified if any storm-scale circulation generated today drifts nearby Wednesday. Nocturnal storm chances look small tonight, but some of the high res models show storms persisting Wednesday night in the southern Great Basin. Temperatures will remain below normal thanks to the deep moisture and cloud cover. .LONG TERM...Thursday through the weekend. Continued southerly flow is expected across the region through the weekend. While thunderstorms are possible Thursday afternoon, models continue to highlight the Friday through Sunday period as period of potentially higher impact monsoonal weather. PWAT increase across the region to over 2 standard deviations over normal by Friday afternoon as tropical moisture gets absorbed into mean flow. While its hard to pin point mesoscale features this far in advance, long range models hint at a wave moving around the main flow Saturday into Sunday, which could enhance precipitation chances/coverage. This potential uptick in activity and increased risk of heavy rain leading to flash flooding is highlighted in a few ensembles. ECMWF EFIs shows potential for anomalous QPF through portions of Arizona into eastern portions of southern Nevada FRI-SUN. Model ensembles also show increased probabilities for 100 yr ARIs at times late Friday through Sunday. Finally, some of the clusters show QPF over the ensemble means through the weekend. While details are uncertain at this time, there is an increasing signal for an increased thunderstorm activity, heavy rain, and flash flooding this weekend. What is more certain is the continuation of below-normal temperatures with the persistent moisture and rain chances. && .AVIATION...For Harry Reid...Monsoon moisture will remain in place again today with FEW-SCT12-14k feet and SCT-BKN15-17k feet. Outside of any thunderstorm influences, winds will generally be east around 6-8 kts. Conditions are expected to remain the same Wednesday with scattered afternoon thunderstorms, majority remaining over the higher terrain. For the rest of southern Nevada, northwest Arizona and southeast California...Thunderstorms were dissipating this evening and are not expected to impact TAF sites, though outflow outflow winds from decaying storms could affect TAF sites into this evening. Outside of convection, winds will in general favor diurnal wind trends, except at KBIH where gust southeast winds are expected this afternoon. && .SPOTTER INFORMATION STATEMENT...Spotters are encouraged to report any significant weather or impacts according to standard operating procedures. && $$ SHORT TERM...Morgan LONG TERM...Nickerson AVIATION...Gorelow For more forecast information...see us on our webpage: or follow us on Facebook and Twitter