Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 01/26/20

Area Forecast Discussion...UPDATED
National Weather Service Duluth MN
547 PM CST Sat Jan 25 2020 .UPDATE... Issued at 547 PM CST Sat Jan 25 2020 Update for new 00Z Aviation Discussion below. && .SHORT TERM...(This evening through Sunday night) Issued at 316 PM CST Sat Jan 25 2020 Cloudy skies tonight, with continued chances of light snow over the higher elevations of northern Iron county. Patchy fog will be possible tonight, with some chilly temperatures over north-central Minnesota. An area of surface low pressure, currently situated over northern Lake Huron and is nearly vertically stacked through 250 mb, continues to very slowly translate eastward today. Northerly flow will continue through tonight in the higher levels of the atmosphere, keeping cold temperatures in place. While weak flow is expected near the surface tonight, some lingering chances of precipitation, mainly in the form of snow, will be possible through Sunday morning. A moist air mass will remain in place, which will support ice crystal development aloft within the dendritic snow growth as well as some patchy fog across the region. However, a lack of robust forcing will only lead to some light snow accumulations possible along the Lake Superior snowbelt region, with up to one inch of snow possible from late this afternoon through tonight. A wedge of colder air will skim across our southwestern areas tonight, with lows tonight ranging from around 10 degrees above zero over the Brainerd Lakes region to the upper teens and lower to middle 20s to the east. A secondary shortwave trough will make its way across the Dakotas late tonight and through the day Sunday. We are not expecting any precipitation from this shortwave in our region, but it will help to keep cloudy skies in place for Sunday and Sunday night. The NAM and RAP model soundings both indicate drier air developing in the ice bearing layer aloft, leading to the potential for freezing drizzle over Iron county Sunday. Very little impacts from the icing are expected due to little QPF available. Highs Sunday will warm into the upper 20s and lower 30s. Sunday night lows will fall to the middle teens north to the lower 20s south. .LONG TERM...(Monday through Saturday) Issued at 316 PM CST Sat Jan 25 2020 A messy upper air pattern over the area through much of the upcoming work week will make it difficult to pin down specific times and locations for snow chances, and confidence is not very high. We have an upper level low over the northeast east coast, and a weak but long trough over the west coast, and several shortwaves moving through the west-northwest upper level flow between the two more coherent systems on the coasts. These shortwaves bring small chances for precipitation to the area Tuesday night through Thursday night, with above normal temperatures through the period. The west coast trough axis moves to affect the Northland late in the week, bringing increasing chances for precipitation to the area beginning on Thursday, continuing through Friday and Friday night. Models are not yet in agreement on how this feature moves across the area, with some split flow solutions, and while most of the follow it with a shortwave that moves through the northern stream flow, some keep it too far north to affect us, and others bring more precipitation chances for Saturday. Temperatures warm into Saturday, but the pattern may bring us some colder weather early the following week. && .AVIATION...(For the 00Z TAFS through 00Z Sunday evening) Issued at 547 PM CST Sat Jan 25 2020 Stagnant low pressure over near Sault Ste. Marie will loiter over the region tonight and is forecast to move eastward out of the region on Sunday. Look for MVFR/IFR ceilings to be the norm through the forecast period, with some sites dipping into LIFR CIGS overnight. Think we`ll see areas of fog develop overnight and have a mention of IFR visibility at BRD overnight through late Sunday morning. A few snow showers may affect DLH and HYR, though flight categories will likely be driven by the ceilings. && .PRELIMINARY POINT TEMPS/POPS... DLH 22 30 21 28 / 10 10 0 0 INL 15 30 16 25 / 0 0 0 0 BRD 10 27 18 28 / 0 0 0 0 HYR 24 32 24 32 / 10 10 10 0 ASX 26 32 24 31 / 30 20 10 10 && .DLH WATCHES/WARNINGS/ADVISORIES... WI...None. MN...None. LS...None. && $$ UPDATE...Huyck SHORT TERM...JTS LONG TERM...LE AVIATION...Huyck
Area Forecast Discussion...UPDATED
National Weather Service North Platte NE
742 PM CST Sat Jan 25 2020 .SYNOPSIS... Issued at 326 PM CST Sat Jan 25 2020 H5 analysis from earlier this morning had an area of closed low pressure over northeastern Indiana with a trough of low pressure extending south into the Florida Panhandle. West of this feature, ridging was present from western South Dakota into southern Manitoba. Immediately west of this feature, a shortwave trough was located over central Montana. Another shortwave was present over northern New Mexico. The latest satellite imagery this afternoon, indicates a broad shield of mid level cloudiness tracking across the Dakotas, as well as central and northern Nebraska. Earlier this morning, areas of fog were present across northeastern portions of the forecast area. That fog has since dissipated. Skies this afternoon are partly to mostly cloudy and 2 PM CST temperatures ranged from 32 at O`Neill to 55 at Imperial. && .UPDATE... Issued at 740 PM CST Sat Jan 25 2020 Cameras and radar suggest isolated sprinkles are underway across northwest Nebraska and will continue for a few hours this evening. A very weak midlevel disturbance will move east tonight and presumably, the sprinkles will affect ncntl Nebraska. && .SHORT TERM...(This evening through Sunday night) Issued at 326 PM CST Sat Jan 25 2020 Over the next 24 hours quiet conditions will persist across western and north central Nebraska. Northwesterly flow aloft and low level westerly winds will lead to mild temperatures across the forecast area. Was initially concerned about fog development in the northeastern forecast area after dense fog occurred in these areas earlier this morning. This morning`s HRRR initialized well with the fog this morning. Utilizing the 12z HRRR sfc visby product, fog will remain just off to the east of the area overnight. Westerly winds will push through the forecast area this evening as well, leading to decreased chances for fog development. Lows tonight will be in the lower to middle 20s. Skies will remain mostly clear to partly cloudy on Sunday as the forecast area will be south of an approaching shortwave and cold front. Winds will remain westerly through Sunday afternoon facilitating good mixing and downslope conditions. This will lead to highs in the lower 40s in the east, to the mid 50s in the southwest. By Sunday night, a closed low will track southeast across eastern South Dakota into western Iowa, forcing a back door cold front into the forecast area from the northeast. The fropa will be dry as forcing for pcpn will be well northeast and east of the area. .LONG TERM...(Monday through Saturday) Issued at 326 PM CST Sat Jan 25 2020 Temperatures behind the front will be much cooler for Monday with highs ranging from around 30 in the northeast, to the lower 40s in the southwest. By Monday evening, a shortwave trough will dive south southeast along the front range of Colorado and Wyoming, as well as the Nebraska Panhandle. Aided by easterly upslope winds, light precipitation will develop in the panhandle and spread east into west central and southwestern Nebraska Monday night. The NBM initialized pops for the entire forecast area Monday night. After collaborating with OAX and GID, it was decided to cut pops out of our northeastern and far eastern forecast area Monday night and keep them focused across west central and southwestern Nebraska. A split flow regime will persist through the middle and end of the work week. A system will track across the desert southwest into the southern plains Thursday. At the same time, a shortwave trough will lift across the Dakotas. Right now, will retain a dry forecast, however, pops may need to be inserted in the Thursday/Thursday night time frame if the models continue to indicate this northern stream shortwave. A warm front will push into the region Friday with a broad ridge of high pressure building into the region next weekend. Other than some slight chance pops for Friday night, dry conditions will carry over into next weekend with much warmer temperatures. && .AVIATION...(For the 00Z TAFS through 00Z Sunday evening) Issued at 544 PM CST Sat Jan 25 2020 VFR is generally expected across western and north central Nebraska tonight through Sunday afternoon. The batch of midlevel clouds and sprinkles across wrn Nebraska will move east and exit the region around 04z this evening. An upper level disturbance across srn Saskatchewan will move southeast tonight and send a cold front into nrn Nebraska late Sunday afternoon. Indications are VFR will prevail as the front moves through but there is a slight chance for MVFR ceilings along and north of highway 20 after 21z Sunday. && .LBF WATCHES/WARNINGS/ADVISORIES... None. && $$ UPDATE...CDC SYNOPSIS...Buttler SHORT TERM...Buttler LONG TERM...Buttler AVIATION...CDC
Area Forecast Discussion
National Weather Service Marquette MI
525 PM EST Sat Jan 25 2020 .SHORT TERM...(This evening through Sunday) Issued at 334 PM EST SAT JAN 25 2020 RAP analysis shows a 1007mb, close to vertically stacked, low across eastern Upper Michigan. As this low has been slowly lifting through the Great Lakes region, periods of snow, fog, and drizzle have worked their way across the UP. Dewpoints across the cwa remain close to 32F this afternoon, as temperatures have climbed to near 35 across central and eastern UP. As temperatures have climbed, this morning`s fog has slightly lifted...but ample moisture in the low levels remains, as do the low ceilings. As the low continues to slowly depart to the east tonight, model reflectivities suggest additional round of -SHSN to move across the UP...this time from west to east. There are slight discrepancies across the model soundings wrt cloud ice, but where models show - shsn, saturation through the DGZ is present. Due to this, went with slight -DZ/-FZDZ chances, but mainly stuck with snow for the hydrometeor. With that, expecting 1 to 2 inches of fresh snow tonight, with most of those amounts remaining north and in the higher terrain. Elsewhere, up to an inch as temps in the mid 30s will keep initial precip as drizzle. Fog chances will remain tonight with a ripe snowpack and ample low-level moisture as temperatures begin to fall tonight. Tomorrow, a few snow and drizzle chances will remain...but mainly along Lake Superior as models suggest. High-res guidance suggests Lake Superior enhancement, but with 850 temps remaining in the -5 to -6C remains slim for most of the chances. With that, have left most of the accumulations low, and in the morning. These chances will bring snow accumulations of a half an inch or so, but low clouds should hang on through the day with lingering moisture. .LONG TERM...(Sunday night through Saturday) Issued at 310 PM EST SAT JAN 25 2020 Overall, a fairly quiet weather week is on tap as the main, pesky cutoff low continues to exit the region early next week. A few shortwaves look to dig south across the region through mid-week, but surface ridging starts to dominate mid-week as split flow develops and upper-level ridging builds across the Upper Great Lakes. Temperature wise, expect the mild January temperatures as of late to persist, with a brief, subtle cool down mid-week, and the return of above normal temperatures to end next week. Towards the end of next weekend, deterministic models do show the potential for some colder air working into to the region, but overall there is uncertainty in where, when, and how cold. Overall, we`re going to continue to put up with these above normal-temperatures for much of the upcoming week. Sunday night into Monday, shallow, upslope northerly flow looks to persist across the region with 850mb temps hovering around -5 to - 6C. This lack of colder air aloft, and further examination of forecast soundings supports more freezing drizzle than snow showers. So have trended the forecast from a freezing drizzle/snow mix Sunday evening to straight freezing drizzle overnight into Monday morning. Additional examination of the probability of cloud ice among the deterministic models all showing no ice also aided in this decision. Have kept QPF on the very low end (0.01 to 0.02`` at most) and still end up getting a bit more ice accretions in the forecast than would like, so expect at least a glaze of ice to be possible, especially on elevated and untreated surfaces across the higher terrain out west and in the north-central. Elsewhere, conditions look to remain mostly dry, especially across the south-central. As we progress throughout Monday, 850mb flow backs more westerly with some slightly colder air moving into the region. This should help transition precipitation back over to light snow later in the day across the upslope regions across the west and north central. The south-central and east look to remain mostly dry right now. Tuesday through Thursday, a train of shortwaves will dig south across the Upper Great Lakes so there will be occasional opportunities for wintry precipitation. Overall, nothing major as these shortwaves look to lack overall moisture with surface high pressure extending southwest from the Hudson Bay area bring in some drier air, after the initial shortwave arrives on Tuesday. Thursday night into next weekend, surface high pressure over the Hudson Bay area shifts east over the Northeast, as a wave over the northern Rockies ejects out over the northern Plains and pivots over the Upper Great Lakes region. This will bring back widespread chances for snow, especially late in the week into next weekend. Much further south, the stream stream/end of this wave looks to keep the Gulf Moisture (and any other tropic connections for that matter) in check, so we will have to see what moisture this system has to work with, and if any lake-enhancement will be possible. Given the current track of this system, the best chance for lake-enhanced snow would be off of Lake Michigan out east in spots. Otherwise, once the system passes, if the colder air behind this system does pan out, we should see the return of lake-effect snow next week. && .AVIATION...(For the 00Z TAFS through 00Z Sunday evening) Issued at 525 PM EST SAT JAN 25 2020 As an area of low pressure continues to slowly lift north through the Great Lakes region and will leave low-level moisture and IFR, to at times LIFR, cigs at all terminals. As this low pressure system begins to move north and east of Upper Michigan tonight, expect -SN to spread across the UP from west to east and slowly taper off by Sun morning. With temperatures hovering around freezing and the snowpack remaining ripe, fog and mist will remain possible at all terminals with IFR vsbys prevailing through most of the forecast period. && .MARINE...(For the 4 PM Lake Superior forecast issuance) Issued at 334 PM EST SAT JAN 25 2020 Northerly winds approaching 25 knots will be possible tonight into tomorrow afternoon as a low pressure system exits the Great lakes region. Winds then remain light and below 20 knots through the forecast period. && .MQT WATCHES/WARNINGS/ADVISORIES... Upper Michigan... None. Lake Superior... None. Lake Michigan... None. && $$ SHORT TERM...JAW LONG TERM...Ritzman AVIATION...07 MARINE...JAW