Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 03/05/21

Area Forecast Discussion
National Weather Service Bismarck ND
934 PM CST Thu Mar 4 2021 .UPDATE... Issued at 934 PM CST Thu Mar 4 2021 There are some hints of fog developing in northwest North Dakota, and to the south and west of the Devils Lake Basin. Based on previous nights` model vs. observation performance of low-level moisture fields, we are very reluctant to increase messaging of fog potential until we see something more prominent. The greatest potential for impactful visibility reductions is across the 4 northwestern-most counties of North Dakota, where snow cover still exists and dense fog is climatologically more common (at Stanley and Tioga). Model consensus for sky cover remains very poor. It is under-performing on high clouds across southwest North Dakota and over-performing on low clouds across northern North Dakota, although there are signs of developing fog in some similar locations. The first several hours were adjusted to more closely follow observed trends. UPDATE Issued at 622 PM CST Thu Mar 4 2021 Some minor adjustments were made to the coverage of patchy fog tonight through tomorrow morning. The HRRR and RAP visibility fields were relied upon, as they have been trending well with observed surface dewpoints. However, it`s worth noting that all guidance, especially non-HRRR/RAP solutions, has been far too aggressive with both the coverage and duration of low stratus and fog the past few nights. For this reason, we also trended sky cover down with this update. Even though our forecast grids will contain 30-70% sky cover for much of the area, think that most locations will either be completely overcast or completely clear at any given time. && .SHORT TERM...(This evening through Friday) Issued at 113 PM CST Thu Mar 4 2021 Low stratus and fog tonight and continued mild temperatures tomorrow highlight the short term forecast. Tonight, easterly surface flow will bring in a shallow layer of moisture (enhanced by continued snow pack melting) across central and eastern ND. Forecast sounds depict low stratus between 500-1000 feet AGL and some fog as a result. There is some uncertainty as to the extent and duration of the stratus/fog. Some short-term models want to take it as far west as Dickinson and leave Jamestown clear, while the majority maintain a further east solution. How long clouds/fog persist will play a significant role in temperatures tomorrow. We still maintained a warmer forecast than what the NBM is providing due to its continued cold bias, but we elected to go below the higher end thresholds we`ve been trending with as of late. We still expect the southwest will see temperatures in the 60s tomorrow, but further east where cloud cover is more likely and more likely to linger longer, temperatures could struggle to get out of the 40s to lower 50s. .LONG TERM...(Friday night through Thursday) Issued at 113 PM CST Thu Mar 4 2021 Mild and dry conditions continue through much of the long term before a potentially more active pattern sets up next week. Saturday will likely be the warmest day through the next week as an upper-level ridge axis moves directly overhead. Therefore, maintained higher than straight NBM temperatures which brings widespread upper 60s into portions of the west and widespread upper 50s to low 60s everywhere else, except for the Turtle Mountains. This is slightly cooler than the previous forecast as the cold front appears to be slightly delayed. This means compressional warming will be maximized a bit further west and a southeasterly (which doesn`t mix down as well as southwesterly) wind will be favored all day. Winds will be quite breezy Saturday afternoon with southeasterly winds around 25 mph gusting to 35 mph. This may lead to near critical fire conditions across the southwest Saturday afternoon where temperatures will be in the upper 60s, relative humidity around the low 20s and winds around 30 mph. Sunday will not be as warm, but highs should remain well above normal with widespread readings in the upper 40s to upper 50s. The flow becomes more zonal on Monday as a broad western trough approaches Tuesday into Wednesday. This could be the start of a more active period. The 12z suite of deterministic global models have trended towards the flow staying split over the Dakotas before phasing across the Great Lakes, keeping the strongest cyclogenesis well to our east. Still, warm air advection associated with the northern wave stream would still bring us a brief period widespread precipitation in this scenario, but the impacts would be fairly tempered. The 12z ensemble guidance has shifted their favored storm track a bit north and lowered their expectations of more meaningful precipitation. Overall, expectations remain low in this system producing impacts or much needed rain, but a great deal of uncertainty remains so there is still the possibility however small it might be. && .AVIATION...(For the 00Z TAFS through 00Z Friday evening) Issued at 622 PM CST Thu Mar 4 2021 Patchy fog with associated LIFR ceilings may develop across much of western and central North Dakota tonight through Friday morning. Confidence in impacts at any given terminal remains low, so have opted to include VCFG and SCT003 mentions for this set of TAFs. Otherwise, VFR conditions and light easterly winds are expected through the forecast period. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...Hollan SHORT TERM...AJ LONG TERM...AJ AVIATION...Hollan
Area Forecast Discussion
National Weather Service Dodge City KS
549 PM CST Thu Mar 4 2021 ...Updated aviation discussion... .SHORT TERM...(This afternoon through Friday night) Issued at 1200 PM CST Thu Mar 4 2021 Closed cyclone tracking across southern Colorado right on schedule at midday, with the associated surface low organizing over SE Colorado. Forcing for ascent and diffluence aloft continue to increase at midday, and southeast winds will continue to increase for the next several hours, gusting over 30 mph. Paltry moisture advection continues, with dewpoints now into the upper 30s. There is not much moisture to tap upstream in Oklahoma; only expecting low to mid 40s into SW Kansas by late afternoon and evening. Additional moistening is ongoing from aloft, with widespread virga already present visually and on radar. 12z NAM is focusing its instability axis (MU CAPE of 500-1000 J/kg) from roughly the Dodge City vicinity to the Red Hills by early this evening. This is actually a very favorable setup for severe convection, given the diurnal timing, lift/forcing, and shear....minus the needed moisture and instability. Some strong to marginally severe low topped storms/supercells are plausible this afternoon and evening, as mid level cold advection continues over minimal boundary layer moisture. Marginal hail (quarters or less) and wind gusts (< 60 mph) are possible. Measurable rain will be scattered around with this activity, but confidence on the widespread beneficial rainfall remains focused overnight, in the deformation zone north of the southeast-digging mid level cyclone as it tracks into western Oklahoma by sunrise Friday. Storm total QPF grids still show a widespread 0.25-0.50 inch rainfall, and HRRR guidance suggests most of this will fall between midnight and sunrise Friday. Temperatures will remain well above freezing through this entire event, and all precipitation will fall as rain. Winds will be quite elevated and gusty from the northeast during the rain, gusting over 30 mph. Temperatures sunrise Friday in the upper 30s and lower 40s. Light rain will linger across especially the southern zones for the first few hours of Friday morning, with some more measurable QPF mainly south of US 50. Widespread stratus and low clouds will prevail Friday morning, but rapidly dissipate through the afternoon amid strong subsidence. Models do show minimal cold advection behind the departing trough, with a net decrease of about -3C at 850 mb versus Thursday, but with plenty of early March afternoon sun, mid to upper 50s are still expected. NE winds of 15-25 mph will gradually weaken through late afternoon. .LONG TERM...(Saturday through Thursday) Issued at 135 PM CST Thu Mar 4 2021 The forecast is completely dry, Saturday through at least Tuesday. Broad high pressure ridging will provide for a fantastic early spring weekend. Afternoon temperatures will be recovering through the 60s Saturday and Sunday, but the typical Kansas south winds of 20-30 mph will be blowing both afternoons. Still a bargain for early March. More of the same Monday, windy and warm, as flow aloft begins to trend SWly in response to an expansive long wave trough arriving in western North America. Afternoon temperatures in the lower 70s. We continue to monitor Tuesday for potentially extreme danger of wildfire spread. Model consensus places primary lee cyclone (<996 mb) in the vicinity of SW Nebraska 6 pm Tuesday, with a strong dryline trailing southward through the high plains. Pressure gradients will be tight, with the tightest gradients likely east of the dryline in central Kansas (850 mb winds of 45-50 kts). Still, locations behind the dryline will likely be windier drier and warmer than any guidance, and will likely have fire weather headlines Tuesday. Afternoon temperatures from the NBM were near 80 and were accepted. Synoptic pattern appears decidedly springlike mid next week, with a strong established dryline and convective potential given strong SWly flow aloft. Expansive longwave trough across the Rockies Wednesday will edge out onto the plains late Wednesday. Details will waffle this far out, but the deterministic 12z ECMWF currently suggests severe convection late Wednesday from the southeast zones northeast through central/NE Kansas. This severe potential will have to be watched closely, given a strong SWly jet aloft and an open gulf, but climatology says most will be southeast of SW Kansas. Cold frontal passage is expected Wednesday night, followed by cooler/more stable air Thursday. && .AVIATION...(For the 00Z TAFS through 00Z Friday evening) Issued at 549 PM CST Thu Mar 4 2021 An upper level low pressure system over southeast Colorado will move into eastern Oklahoma by midday Friday. Initially, the area will see VFR cigs and scattered showers with isolated thunderstorms this evening. MVFR to IFR cigs will develop late this evening through the overnight hours along with a switch to northeast winds. Areas of rain will increase in coverage across central/west central Kansas late this evening and spread southward through southwest Kansas late tonight into early Friday. Conditions will be improving across the area from north to south late Friday morning into Friday afternoon as the upper level system pulls away from the region. && .PRELIMINARY POINT TEMPS/POPS... DDC 41 61 32 65 / 90 40 0 0 GCK 40 59 30 64 / 90 30 0 0 EHA 39 57 31 64 / 40 60 0 0 LBL 38 57 31 63 / 50 60 0 0 HYS 40 60 30 67 / 90 20 0 0 P28 43 59 34 65 / 90 60 0 0 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Turner LONG TERM...Turner AVIATION...Gerard
Area Forecast Discussion
National Weather Service Marquette MI
534 PM EST Thu Mar 4 2021 .SHORT TERM...(This evening through Friday) Issued at 241 PM EST THU MAR 4 2021 Current RAP analysis and GOES WV imagery show an upper level low over Quebec today and will likely hang around through Friday that will continue to bring weak northerly flow over the Upper Peninsula, resulting in some flurries or very light snow showers along the Lake Superior shoreline. This has gradually diminish throughout the afternoon with dry air aloft moving over the area. Soundings show an inversion around 850-900mb that will help dry things out which has occurred earlier than anticipated and will have winds back a bit more to the northwest and this will bring slight chances of light snow showers east of Munising late tonight or early Friday morning. Temps at 850mb on Friday morning will be between -10C to -12C which will support light snow showers over those areas through the morning hours. Not expecting much in terms of accumulations with generally around a half-inch or less. Elsewhere, it will continue to remain dry with clouds over the north and east and partly to mostly sunny skies across the south and west. Temperature wise, it will be pretty similar to what we saw for highs yesterday with mainly 20s across the north and east with 30s over the south and west along the WI border where there will be more sunshine. Seeing some breaks in clouds earlier than anticipated and that has allowed temps to rise quickly over the west and as a result, have raised highs for today. Lows tonight could get chilly again over the interior west similar to last night where some spots fell below zero with mainly clear skies at Wakefield and Watersmeet. Would not be surprised if this were to occur again tonight. Highs Friday will be a little warmer than today with widespread 30s and maybe a few low 40s over the far south. .LONG TERM...(Friday night through Thursday) Issued at 515 PM EST THU MAR 4 2021 Overall, quiet weather will prevail across Upper MI thru early next week. This quiet period will be the result of sharp ridging/strong positive height anomalies developing from the High Plains to Hudson Bay thru Sat. The ridge will then shift across the western Great Lakes on Sun, followed by a weak shortwave trough passage on Mon and then rebuilding of a ridge into the Great Lakes for Tue. Heading into the middle of next week and on into the mid Mar period, there are indications for an active pattern to develop, featuring at least a couple of waves dropping into the western U.S. and then ejecting ne across the Plains. The first wave will arrive midweek with majority of the pcpn for Upper MI probably being rain. A second wave may affect the Great Lakes region late in the week. Temps next week will trend overall above normal in this pattern, but will be dependent on the track of shortwaves/associated low pres systems lifting across the central U.S. If passing to the w of Upper MI, some warm days will be in the offing. With the first wave likely passing w of Upper MI, it looks like some 50s will be observed Mon and especially Tue, at least over western Upper MI. Wed could be warm as well, depending on timing of cold fropa associated with the first wave. Beginning Fri night into Sat, it looks like another shortwave will drop sse, passing across far eastern Lake Superior. Several of the models indicate CAA may drop 850mb temps back toward -13C across eastern Lake Superior which could result in around round of flurries off the lake into the eastern fcst area late Fri night/Sat morning. Under near calm wind and mostly clear skies over the w, temps Fri night will fall back into the single digits above 0F in the interior. Expect mainly teens elsewhere. Highs Sat should be similar to Fri ranging from around 30F north central and east to near 40F along the Wisconsin-Michigan stateline. Sfc high pres ridge will finally shift e across the area Sat night. Central and especially the eastern fcst area should be under the ridge axis and near calm wind long enough for temps to fall back into the single digits above 0F in the interior. A few spots could slip blo 0F. As shortwave trough moves out over the Canadian Prairies and northern Plains on Sun, the mid-level ridge will shift across the western Great Lakes. As the associated sfc high pres ridge pushes e of the area, southerly winds be the rule. High temps should push well into the 40s, maybe above 50F, over portions of western Upper MI. Expect 30s for much of the east half. The northern Plains shortwave trough will then move across the area late Sun night/Mon morning. Given limited moisture and weak forcing could maybe see some light shra across the north and east with this feature. Will maintain slight chc pops from the Keweenaw into the eastern fcst area. Broader mid-level ridging will then develop over the eastern U.S. into Tue as mid-level troughing expands across the western U.S. Lead shortwave with this western trough will begin to eject out across the Plains, but should remain far enough to the w for mostly dry weather to linger into Tue. Temps Mon and especially Tue, when best WAA is occurring ahead of the incoming Plains system, will likely rise into the 50s F over portions of western Upper MI. However, Mon could be a surprise warm day with temps well into the 50s across portions of the w half of the fcst area as skies clear after shortwave passage in the morning. Temps will be coolest closer to Lake MI both days. The shortwave ejecting out of the western CONUS trough will support a low pres wave which model consensus indicates will likely pass just w of the fcst area as it lifts ne on Wed. GFS is one of the few models showing the low passing over the central U.P. Pcpn associated with this system will spread into the fcst area in the Tue night/Wed time frame. At this point, it appears this will be mainly a rain event. Will turn cooler in the wake of the system on Thu with some lingering -shsn in the morning. && .AVIATION...(For the 00Z TAFS through 00Z Friday evening) Issued at 534 PM EST THU MAR 4 2021 VFR conditions will continue through the period at IWD and CMX. SAW could see some MVFR conditions Fri morning...otherwise it will be VFR there. && .MARINE...(For the 4 PM Lake Superior forecast issuance) Issued at 241 PM EST THU MAR 4 2021 Wind will generally remain 20 knots through early Friday as a surface high pressure continues to dominate the Great Lakes region. Winds will increase to around 20 knots over the east half of the lake by Friday afternoon and evening with gusts to 30 knots and can`t rule out a few gale force gusts as well. Winds will slowly diminish through the day Saturday, falling below 20 knots by Saturday afternoon. Winds will shift to more of a southerly flow by Sunday as the ridge shifts east a little and could have another quick shot of winds of 20 to 30 knots Sunday afternoon and evening before falling under 20 knots Monday. && .MQT WATCHES/WARNINGS/ADVISORIES... Upper Michigan... None. Lake Superior... None. Lake Michigan... None. && $$ SHORT TERM...JH LONG TERM...Voss AVIATION...07 MARINE...JH
...Update to aviation forecast discussion...

.DISCUSSION... Issued at 259 PM CST Thu Mar 4 2021 It has been another pleasant day weather-wise with temperatures reaching the low 70s for a second day in a row. Light rain will be possible for some tonight/early tomorrow. Otherwise, warmer than average temperatures remain the rule this forecast package. As of this afternoon, a mid-level closed low was spinning over Colorado. Clouds associated with that system were evident on visible satellite imagery over western KS, and radar was showing some shower activity and even a few lightning strikes in that part of the state. Closer to home, skies remained mainly sunny with a warm and continued very dry air mass in place. Mixing of the PBL has been allowing drier low level air to mix down to the surface, effectively dropping dew points and relative humidity values again this afternoon. As such, widespread very high fire danger will remain in place until after sunset when RH values increase and breezy southeast winds subside. The storm system over CO will pivot southeastward into Oklahoma by tomorrow morning. Light rain will continue to be possible through that timeframe, primarily over central and southeast KS. The rain may clip the extreme southern and southwestern CWA tonight, but chances remain on the low side due to weak lift and lack of deep layer moisture -- RAP and HRRR profiles both show a layer of dry air from the surface up through about 700 mb. Cloud cover associated with tonight`s system will clear through the day tomorrow. The absence of any impactful systems this weekend will allow for continued enjoyable conditions. The pattern is expected to become increasingly active next week. Long range models are in better agreement today with the timing and placement of a cold front that could impact the forecast area midweek. Theta-e advection ahead of the boundary would increase instability and could result in thunderstorms developing along the front late Wednesday or early Thursday. Trends will be monitored to fine tune details of the as this timeframe approaches. && .AVIATION...(For the 00Z TAFS through 00Z Friday evening) Issued at 530 PM CST Thu Mar 4 2021 Conditions are expected to remain VFR through the period. Winds weaken this evening becoming east-northeasterly under 10 kts through the day Friday. Clouds increase tonight as a system tracks across western Kansas although associated precip and MVFR cigs are expected to remain south of terminals. && .FIRE WEATHER... Issued at 259 PM CST Thu Mar 4 2021 Very high fire danger continues this afternoon. As expected, afternoon RH values have fallen to around 20 percent across much of the region and southeast winds have increased, especially in central Kansas where gusts exceed 20 mph. Conditions will not improve until just after sunset, at which time the RH should start to increase and winds should subside slightly. && .TOP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ DISCUSSION...Teefey AVIATION...Flanagan FIRE WEATHER...Teefey