Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 04/14/20

Area Forecast Discussion...CORRECTED
National Weather Service Cheyenne WY
923 PM MDT Mon Apr 13 2020 .UPDATE... Issued at 846 PM MDT Mon Apr 13 2020 CYS 88D radar indicated scattered snow showers developing between Cheyenne, Horse Creek and Federal, as well as over the South Laramie Range. Shower coverage has decreased somewhat since late afternoon, and recent hi-res models progs shower activity to move south of the CO/WY border after 06Z. Additional accumulations this evening will be light, generally up to an inch. After the snow ends, skies will become mostly clear. Travel concern overnight through early Tuesday morning will be areas of black ice as roadway temperatures fall into the upper teens and 20s. Lowered PoPs and tweaked sky grids for the evening update. && .SHORT TERM...(This evening through Tuesday) Issued at 255 PM MDT Mon Apr 13 2020 In the near term our main concern is with potential of banded snow showers that will form up along the south Laramie Range through late evening and the potential with temperatures to drop anywhere from 3 to 5 inches of snowfall in a few hours. Latest NAM Nest and HRRR still point to this potential and have been decent performers of late catching these trends. For now, and after collaboration with WYDOT on road temperature trends, think roads could become slick and snow covered this evening along sections of I-80 between Cheyenne and Laramie when potential for higher rates of snowfall will be in play. A Winter Weather Advisory has been posted through 3 AM tomorrow morning for the south Laramie Range to include higher elevations of Interstate 80 between Cheyenne and Laramie. Kept temperatures a few degrees below guidance tonight given models have been colder overnight and think that trend will hang on again at least one more night. Less precip and snow showers tomorrow with a break in the active pattern then we set our sights on the system coming down in the northwesterly flow mid-week. .LONG TERM...(Tuesday night through Monday) Issued at 255 PM MDT Mon Apr 13 2020 Models have some consistency on depicting a strong upper system coming down into Wyoming Wednesday bringing our next significant shot at snow across eastern Wyoming and western Nebraska Wednesday into Thursday night. Some of the models are depicting several inches of snowfall (up to 2 feet) in the southern Wyoming mountains with Winter Storm Warning criteria (6 inches or greater) 5000-7000 ft elevation and more typical advisory criteria (<6 inches) lower elevations. Given the track record of the models of aiming high in the extended and pulling up short as we close in to game time, we are thinking we will hold off on any issuances of Winter Storm Watches at this point, take another look on the 00Z cycle, and then consider watches on the morning forecast for Tuesday. From what we see right now, areas closer to the 6 inch or greater amounts would be in the mountains and along and just east of the Laramie Range down to about 5500 ft elevation. Stay tuned for additional details and potential Winter Storm Watches. Looking further still looks like the weekend will still trend a bit warmer although there could still be a few showers around. && .AVIATION...(For the 00Z TAFS through 00Z Tuesday evening) Issued at 521 PM MDT Mon Apr 13 2020 Wyoming TAFS...VFR, except for occasional MVFR at Laramie and Cheyenne until 02Z. Wind gusts to 20 knots at Rawlins until 03Z, then gusts to 35 knots at all terminals after 15Z Tuesday. Nebraska TAFS...VFR. Wind gusts to 28 knots until 03Z, then gusts to 35 knots after 15Z Tuesday. && .FIRE WEATHER... Issued at 255 PM MDT Mon Apr 13 2020 Fire weather concerns remain low due to recent precipitation and low winds right now. Relative humidity minimum values stay elevated above 25% the next 72 hours. Continuous chances of precipitation this week will help reduce fire level concerns over the area. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...Winter Weather Advisory until 3 AM MDT Tuesday for WYZ116-117. NE...None. && $$ UPDATE...Jamski SHORT TERM...Garmon LONG TERM...Garmon AVIATION...Rubin FIRE WEATHER...Garmon
Area Forecast Discussion...UPDATED
National Weather Service Midland/Odessa TX
921 PM CDT Mon Apr 13 2020 .UPDATE... High wind warning has expired for GDP Mtns. && .DISCUSSION... High wind warning has been allowed to expire. West winds briefly increased, but further concerns have ended. Still looks unseasonably cold tonight. Radar shows that light precip is farther s than models have generally indicated and light precip is still possible in nrn Lea Co and nrn PB. RAP sounding not very supportive of winter precip across the n, but NAM12 is a little moreso, but either way it should be light. && .PREV DISCUSSION... /issued 643 PM CDT Mon Apr 13 2020/ DISCUSSION... See aviation discussion below. AVIATION... West winds were increasing across the far western areas and may push into CNM briefly. Otherwise e winds will back to ene or ne thru the night with another surge of surface high pressure. MVFR CIGS are expected to develop starting around 10Z at MAF and persist most of the day, except at CNM. PREV DISCUSSION... /issued 238 PM CDT Mon Apr 13 2020/ DISCUSSION... Upper pattern has a broad trough extending southward from a low in Canada down across the middle of the country. This low will wobble east but the trough will be reinforced by another lobe rotating down across CA Tuesday. A flat ridge sets up over the southern tier of states by Thursday as a closed low works down the West Coast late in the week. This low will come ashore Srn CA late Friday and quickly move east and track across the region Sunday. Have sunny skies over the area in post frontal conditions with an easterly wind reinforcing the front tonight as surface ridge builds southward. This will result in another very chilly morning Tuesday. Many of the same areas that saw freezing temperatures this morning could see freezing temperatures again tomorrow morning. Temps will be slow to recover tomorrow with an upslope east wind and some clouds moving in... highs tomorrow will be well below normal and range from the 40s and 50s east of the Pecos... to the 60s and 70s along and west of the Pecos. Temps should not be as cold Wednesday with highs in the 80s back in the forecast by Thursday. A High Wind Warning remains in effect for the Guadalupe Mountains above 7000 ft. Considered adding the rest of the Guadalupes to the warning but latest observation from GDP only shows 7kts so left warning as is. Have a chance of rain/snow mix brushing Lea county tonight as a shortwave moves across but expecting very little from it. A low possibility of some light rain over the northern CWA again Tuesday night. && .PRELIMINARY POINT TEMPS/POPS... Big Spring 33 50 38 62 / 0 0 10 10 Carlsbad 36 62 42 69 / 10 0 10 10 Dryden 45 68 49 67 / 0 0 10 10 Fort Stockton 42 65 43 67 / 0 0 10 10 Guadalupe Pass 36 59 38 63 / 0 0 10 0 Hobbs 32 54 36 63 / 10 0 20 10 Marfa 36 64 38 71 / 0 0 0 0 Midland Intl Airport 34 54 38 63 / 0 0 10 10 Odessa 34 55 38 64 / 0 0 10 10 Wink 37 61 41 68 / 0 0 10 10 && .MAF WATCHES/WARNINGS/ADVISORIES... NM...None. TX...None. && $$
Area Forecast Discussion
National Weather Service Melbourne FL
1015 PM EDT Mon Apr 13 2020 .DISCUSSION... The story of the day has been the hot temperatures across east central FL and windy conditions along the coast. All of our climate sites broke their daily records for the day. Vero Beach also broke the daily record for the month of Apr after it reached 97 degrees just before 5 pm. Then after 6 pm, a narrow line of clouds and showers developed to the northeast of Deland and moved offshore. As it moved to the northeast, it stayed just south of Daytona Beach airport and temperatures dropped from 90 degrees to 79 in 20 minutes. The HRRR model is showing convection to the north of our forecast area overnight with just a few light showers that could move over northern Lake and Volusia. For that, POPs were slightly increase to 15-20% overnight. Elsewhere, for the rest of the night, partly cloudy skies are expected. Low temperatures tonight will drop to the lower 70s and upper 60s. && .AVIATION... Winds dropped late this afternoon and will remain below 10 kt overnight generally from the south to southwest. After 14/06Z, low clouds with bases at 010-015 will possibly affect some of the terminals lifting after sunrise. By morning, winds will increase from the SSW to 10-15 kt and gusts to 20 kt. By late morning/early afternoon, a SE sea breeze of 15-20 knots will develop and affect the coastal terminals. && .MARINE... Winds at Buoy 41009 have dropped to below 15 knots as of 10 pm while at 41010 there were at around 20 knots. Therefore, the advisory for small craft was allowed to expire but small craft should continue to exercise caution overnight across the offshore waters as winds continue to subside. Seas will also continue to subside from 4-6 ft to 2-4 ft. && .PRELIMINARY POINT TEMPS/POPS... DAB 71 90 69 86 / 20 30 20 50 MCO 72 93 72 90 / 10 20 20 30 MLB 74 90 73 89 / 0 30 20 30 VRB 73 91 71 90 / 0 20 20 30 LEE 74 91 71 88 / 20 20 20 50 SFB 73 92 70 90 / 10 20 20 40 ORL 74 92 72 90 / 10 20 20 40 FPR 71 91 72 91 / 0 20 20 30 && .MLB WATCHES/WARNINGS/ADVISORIES... FL...None. AM...None. && $$ Negron/Weitlich
Area Forecast Discussion
National Weather Service Marquette MI
809 PM EDT Mon Apr 13 2020 .SHORT TERM...(This evening through Tuesday) Issued at 432 PM EDT MON APR 13 2020 WV imagery and RAP analysis indicated a mid/upper level low over northwest Ontario with a broad trough through the central CONUS. The shortwave trough that supported the heavy snow has moved off well to the north and east of Lake Huron. A weak upstream shrtwv near the mid level low was located over south central Manitoba. At the surface, the tight pres gradient over the region was gradually weakening as the 983 mb low south of James Bay continues to lift to the northeast. As much drier 850-700 mb air spreads through most of Upper Michigan, the more persistent snow showers have diminished. A stronger LES bands has shifted slowly eastward this afternoon to near Grands Marais to Newberry as winds backed. Diurnal sct -shsn have developed over most of the area as 850/700 mb temps have dropped to around -11C/-22C. Winds have diminished since early afternoon but were still gusting to 30-35 mph in most locations. However, winds at KCMX and KP53 were still gusting to around 40 mph. Tonight, with the loss of daytime heating the sct -shsn will dissipate this evening. However, convergent wnw flow combined with lingering deeper moisture and 850 mb temps to around -12C will provide enough instability for some LES into northeast Upper Michigan, east of Munising. Additional snowfall amounts of 2 to 4 inches may be possible, especially near Grans Marais. Confidence in the details regarding the development of location of any stronger band(s) is low. Tuesday, as the Manitoba shrtwv pivots toward the area and a weak sfc trough develops, expect mainly inland sct -shsn to redevelop as diurnal heating increases and 850 mb temps remain near -13C. Temps will remain well below average for mid April with highs only to around 30 north and the mid 30s south. .LONG TERM...(Tuesday night through Monday) Issued at 410 PM EDT MON APR 13 2020 Expect below-normal temperatures to prevail through the end of the week as the Upper Great Lakes remains under the influence of northwest flow featuring a number of shortwaves rotating down across the region. Towards the end of the week/early weekend temperatures should gradually rebound to near or slight above normal. Don`t expect this trend to persist through, additional shortwave energy arriving late weekend/early next week look to bring back additional shots of colder air. Wednesday through Thursday, a couple of shortwaves will drop south across the region accompanied by a few surface troughs. These waves look to dig south during the morning/afternoon hours each day, thus there should be a daily diurnal uptick in shower activity inland from the Great Lakes. Daytime highs on Wednesday look to top out around the upper 20s to low/mid 30s, thus any shower activity should remain mostly light snow. On Thursday, temperatures warm a bit further with low to upper 30s. The fresh addition to the snowpack, coupled with colder air aloft should allow for chilly overnight lows during this time period where winds are lighter and cloud cover is less expansive across the interior parts of Upper Michigan. Friday there is a bit more uncertainty in how precipitation chances play out as we find ourselves sandwiched between low pressure to our north and surface ridging to our south. Models don`t agree with timing of the next shortwave, so the forecast for Friday may change as we get closer to include mentions of day-time showery activity. Next weekend, there should be period of drier weather as flow becomes zonal ahead of additional upper-level energy progged to track across the region. Return flow will squeeze northward and allow temperature to warm into the upper 40s/lower 50s. Along with this warm up, should be fairly breezy conditions ahead of the cold front progged to drop south across the region Saturday night/Sunday morning. An area of showers is expected to develop ahead of and along the front as it moves south across the region. Precipitation should remain mostly rain, but could switch over to snow as colder air moves in behind the front. && .AVIATION...(For the 00Z TAFS through 00Z Tuesday evening) Issued at 808 PM EDT MON APR 13 2020 VFR conditions will likely prevail thru this fcst period at KIWD/KCMX/KSAW. However, there may be a few brief shsn at KIWD over the next few hrs, potentially dropping conditions very briefly to MVFR or even IFR. In addition, there may be some flurries late tonight/Tue morning at KCMX, but don`t expect conditions to fall out of VFR. Finally, diurnally driven shsn are expected Tue aftn, potentially impacting any of the terminals. Some of these shsn may lead to very brief bouts of IFR conditions. Gusty winds will diminish this evening at KIWD/SAW, but will be slower to diminish at KCMX. Gusty winds to 20-30kt will return during Tue with the strongest gusts at KCMX. && .MARINE...(For the 4 PM Lake Superior forecast issuance) Issued at 432 PM EDT MON APR 13 2020 Gales will linger over eastern Lake Superior this evening as the strong low pressure system south of James Bay slowly lifts off to the northeast. A ridge of high pressure will slowly build toward the area Tuesday. However westerly winds to 30 knots will still linger in the cold airmass as troughing remains through the northern Great Lakes. Winds will then diminish to 20 knots Tuesday night and remain below 20 knots through Thursday. && .MQT WATCHES/WARNINGS/ADVISORIES... Upper Michigan... Winter Weather Advisory until 2 AM EDT Tuesday for MIZ085. Lakeshore Flood Warning until 2 AM EDT Tuesday for MIZ006-007. Winter Weather Advisory until 8 AM EDT Tuesday for MIZ006-007. Lake Superior... Gale Warning until 2 AM EDT Tuesday for LSZ249>251-266-267. Gale Warning until midnight EDT tonight for LSZ245-248-265. Lake Michigan... Gale Warning until 11 PM EDT this evening for LMZ221-248-250. && $$ SHORT TERM...JLB LONG TERM...Ritzman AVIATION...Rolfson MARINE...JLB