Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 11/24/17

Area Forecast Discussion
National Weather Service Bismarck ND
931 PM CST Thu Nov 23 2017 .UPDATE... Issued at 929 PM CST Thu Nov 23 2017 Current forecast looks ok. Winds are slowly increasing and the mixing is maintaining and even helping temperatures to rise a bit this evening. Overall the minimum temperatures in the 40s to upper 30s look ok. Wind advisory will begin in the west at 09Z. UPDATE Issued at 629 PM CST Thu Nov 23 2017 Current forecast trending ok with mainly clear skies this evening. No significant changes to previous forecast. && .SHORT TERM...(This evening through Friday) Issued at 308 PM CST Thu Nov 23 2017 A windy Friday highlights the short term forecast. Multiple All-Time Thanksgiving Day records have been broken or tied today across western and central North Dakota as of 330 pm CST. Location.....Observed...November 23 Record..Thanksgiving All Time Dickinson........69...........63 in 1984........65 in 1998 Williston........67...........56 in 2011........56 in 2002 Bismarck.........74...........62 in 2011........62 in 2002 Minot............62...........55 in 1942........57 in 2011 Jamestown........56...........59 in 1942........56 in 2011 A cold front will propagate across western and central North Dakota tonight. Strong winds will develop behind the front late tonight and continue into Friday across western and central North Dakota. The strongest winds are expected in the 10-18 UTC timeframe when isallobaric forcing is greatest with a 6mb/3hr pressure rise behind the front. The 12 UTC NAM/GFS Bufr and 19 UTC RAP soundings depict around 45-50kts to mix at 850 mb. Thus, widespread wind gusts in excess of 40 kts are expected across western and most of central North Dakota, and a Wind Advisory has been issued for most areas. Would not be surprised to see a couple gusts in excess of 50kts immediately behind the cold front. Scattered rain showers are expected tonight into Friday morning with the passage of the front. With steep mid level lapse rates and a warmer overall thermal profile, a thunderstorm or two may be possible. .LONG TERM...(Friday night through Thursday) Issued at 308 PM CST Thu Nov 23 2017 Above normal temperatures highlight the extended forecast. After a relative cool down for Friday and Saturday in the wake of the cold front, although temperatures will still be above normal, another very warm day is possible on Sunday. The 12 UTC NAEFS 850mb mean temperatures climb towards their 99th percentiles once again on Sunday. Thus, well above normal temperatures in the 50s and maybe the 60s are possible for much of western and central North Dakota on Sunday. && .AVIATION...(For the 00Z TAFS through 00Z Friday evening) Issued at 629 PM CST Thu Nov 23 2017 Hazards to aviation include strong surface winds across the state on Friday with the passage of a cold front and some low level wind shear KISN- KMOT Thursday evening. VFR expected at all TAF sites. && .BIS WATCHES/WARNINGS/ADVISORIES... Wind Advisory from 6 AM CST /5 AM MST/ to 6 PM CST /5 PM MST/ Friday for NDZ003-011-012-019>023-025-034>037-042-045>048-050- 051. Wind Advisory from 3 AM CST /2 AM MST/ to 3 PM CST /2 PM MST/ Friday for NDZ001-002-009-010-017-018-031>033-040-041-043-044. && $$ UPDATE...WAA SHORT TERM...PA LONG TERM...PA AVIATION...WAA
Area Forecast Discussion...UPDATED
National Weather Service Duluth MN
835 PM CST Thu Nov 23 2017 .UPDATE... Issued at 835 PM CST Thu Nov 23 2017 Surface low over the Canadian Prairie provinces continues to deepen this evening ahead of a rapidly moving disturbance over the Pacific NW that will move eastward along the northern tier of states for the next 24 hours. Strong pressure falls and and increasingly strong southerly gradient should act to keep winds up more than is typical for the overnight hours tonight, and this combined with rather widespread cloud cover and a continued slow northeastward movement of the surface warm front should lead to steady or slowly rising temps during most of the overnight hours in most areas. A localized area of enhanced lift attributed to mid level frontogenesis over western Lake Superior and northern Wisconsin has led to the development of a rather persistent area of light showers. Spotter reports indicate that this seems to be reaching the ground mainly in the form of rain. However, there continue to be a few transient radar echoes between 35-40 dbz, and underneath those heavier cores, some mixed precip/snow/graupel is possible for the next few hours - but should not amount to much nor affect road conditions in a negative manner with temps above freezing. The two main adjustments to the forecast earlier this evening were to increase PoPs to account for the showers to the east of Duluth, and to raise temps overnight, especially over northwest Wisconsin, where temps will likely be steady or rise a few degrees into the mid-upper 30s now that the surface warm front has passed, despite the snow cover. && .SHORT TERM...(This evening through Friday) Issued at 316 PM CST Thu Nov 23 2017 Main concerns for the short term are the slight chance of drizzle or freezing drizzle in far northeast Minnesota tonight and warm temperatures with rain chances on Friday. Mainly clear skies were found across most of the Northland this afternoon. Warm air advection aloft will continue tonight with 850 mb temperatures already well above freezing for much of the Northland and a thermal ridge farther west over the western Dakotas. Isentropic ascent has produced a narrow arc of clouds from Aitkin County northwest into northwestern Minnesota. Look for that arc of clouds to expand southeastward as the forcing lifts northeast. Considerable dry air below the cloud layer was found across the region with ceilings in the 7 kft range. BUFKIT soundings from the NAM and RAP over northeast Minnesota keep a substantial dry layer in place below the cloud deck, which will limit drizzle/freezing drizzle potential tonight. Have moved the precip mentions farther north with this forecast and raised overnight low temperatures above the consensus blend. A shortwave trough indicated in the RAP analysis and GOES-16 water vapor imagery over Alberta and southern British Columbia will quickly advance across the Canadian Prairies tonight and into Minnesota on Friday. Surface low pressure will scoot eastward across northern Ontario with a cool front sliding through the Northland. Light rain is forecast to develop along and ahead of the front and move through the region. Temperatures aloft will cool behind the front, but a potential for mixed precipitation will hold off until late afternoon or evening. Very mild temperatures are expected with lows tonight from the middle 20s to the middle 30s, 10 to 20 degrees above normal. Continued mild for Friday with highs near 40 north and the upper 40s southwest, 10 to 18 degrees above normal. .LONG TERM...(Friday night through Thursday) Issued at 316 PM CST Thu Nov 23 2017 The Friday system exits the system fairly quickly Friday night, leaving some drizzle/freezing drizzle/snow chances for mainly the Arrowhead and parts of northwest Wisconsin Friday night. This should not have much of an impact as even if we do get these weather types, we may only get some patchy ice accumulations. A weak ridge axis moves across the area on Saturday and Saturday night, with temperatures on the chilly side. Another shortwave will move across Manitoba and Ontario late Saturday night and Sunday, once again bringing a weak trough axis across the area. A few models are producing precipitation, but most of them are drier and have little if any precipitation and have left pops out of the forecast with just an increase in cloud cover. Another ridge slides through the area Sunday night. We are finally beginning to get some consistency early next week, with a longwave trough that swings across the CONUS. The GFS is still more phased than the ECMWF, but much better than model runs in the last few days. This should bring some warm temperatures into the area, with highs rising several degrees above normals. Late Monday and Monday night into early Tuesday some precipitation chances will move through the area behind the surface boundary, so INITIALLY we have rain which then becomes mixed with and becomes all snow. We may see POPs increase in the next few runs as long as the consistence continues to increase. Later in the week confidence remains low, as model differences become more significant. For now we have some chances for snow in the Wednesday night/Thursday time range, with near normal temperatures. && .AVIATION...(For the 00Z TAFS through 00Z Friday evening) Issued at 606 PM CST Thu Nov 23 2017 A rapidly moving disturbance will traverse the area over the next 24 hours, with initially southerly flow and warm advection, and then a rather strong cold front will move across the area the last 6 hours or so of this TAF period, bringing a rapid shift back to northwest winds. The atmosphere is relatively dry in advance of this system, so despite rather strong ascent, precipitation is not expected to be widespread or heavy, but most terminals should experience a period of mainly rain showers during the morning to midday hours on Friday. Low level wind shear is also expected at all terminals through Friday morning, with southwest to west flow between 35-45 knots within a couple thousand feet of the surface. && .PRELIMINARY POINT TEMPS/POPS... DLH 33 44 23 29 / 20 50 10 0 INL 30 42 16 25 / 30 60 20 0 BRD 35 46 27 34 / 20 40 0 0 HYR 33 44 27 32 / 0 50 0 0 ASX 33 46 28 32 / 30 40 10 10 && .DLH WATCHES/WARNINGS/ADVISORIES... WI...None. MN...None. LS...Small Craft Advisory until 6 AM CST Saturday for LSZ121-140>143- 146>148. Small Craft Advisory from 4 AM Friday to 6 AM CST Saturday for LSZ144-145. && $$
Area Forecast Discussion
National Weather Service Marquette MI
721 PM EST Thu Nov 23 2017 .SHORT TERM...(This evening through Friday) Issued at 406 PM EST THU NOV 23 2017 WV imagery and RAP analysis indicated a mid/upper level trough over Quebec and a ridge from the sw CONUS into the nrn plains resulting in nw flow through the nrn Great Lakes. Upstream, a vigorous shortwave trough was moving through the Pacific northwest. At the surface, a ridge from northwest Ontario into Lake Superior was sliding to the east as a 992mb low moves into srn Saskatchewan. A warm front extended southward through the cntrl Dakotas. Vis loop showed mostly clear skies over most of the cwa with some lingering clouds north from moisture off of Lake Superior. Tonight, after a period of additional clearing north this evening as winds back to the southwest, clouds will increase as mid level WAA/isentropic ascent shifts into Upper Michigan. However, any pcpn is expected to remain over northern Lake Superior or northern Ontario. Friday, Rain chances will increase during the morning as the WAA regime strengthens further. However, confidence in pcpn chances is still low given potential of a lingering dry 900-700mb layer, per fcst soundings. The best chance for widespread pcpn will be during the afternoon from west to east as the shortwave and cold front approaches with moderate to strong 700-500mb fgen moving through the cwa. Since moisture inflow will still be limited, QPF values only around a tenth of an inch are expected. The WAA will help push temps into the mid and upper 40s, especially for downslope locations. .LONG TERM...(Friday night through Thursday) Issued at 254 PM EST THU NOV 23 2017 ...Varying temps into next week with light lake effect on Sat... Upper air pattern to start the weekend features broad ridge over western Conus with downstream troughing over Upper Great Lakes and eastern Canada. Shortwave moving through in the troughing aloft will support rain showers late Fri into Fri evening. Lift with shortwave is not very strong so not expecting anything heavy. Could be a bit of drizzle once deeper moisture moves out by late Fri evening but dry sub cloud layer/inverted v look in soundings may just keep it mainly dry at the sfc. Late Fri night into Sat morning, another shortwave moving through along with arrival of polar jet will bring colder airmass across Lk Superior and Upper Michigan. Expect lake effect to increase as H85 temps fall to -10c which will produce sufficient over-water instability with water temps of +4C. Soundings show inversions up to 7kft with temps at inversion top of -13c. Some question on extent of moisture at top of inversion though as GEM is drier than the NAM and GFS. NW flow leading to additional moisture off Lk Superior and daytime heating/instability should allow for expansion of some snow showers and flurries over most of Upper Michigan, except far scntrl forecast area vcnty of southern Menoninee county. Weak cyclonic flow and weak low-level convergence and dry air moving in with approaching high will keep snow accumulations on the light side. Main issue will be that whatever snow is occurring will be blown about since it will be higher SLR type. Soundings indicate tapping into mixed layer winds of 25-30 kts with deepest lake convection over east pulling down gusts over 35 kts. Think the main snow/blowing snow/reduced vsby hazard will be over east where higher coverage of snow showers and strongest winds are progged. Any lake effect and winds diminish steadily from west to east Sat night as subsidence/anticyclonic flow increase as sfc high pressure briefly builds across from northern Plains to the Upper Great Lakes. NW winds, H85 temps staying blo -10c and lingering moisture to H85/4kft will continue to support light lake effect/flurries over eastern forecast area. Even this lake effect will end after midnight with lowering inversions and winds backing to WSW after 09z Sun. Clipper shortwave and weak sfc low slide by north of Lk Superior on Sun. Looks mostly cloudy, especially north with breezy conditions possible, but should be no big weather impacts. Temps should stay cool with low 30s west to upper 30s scntrl and east. Upper ridge builds across on Mon though 12z GEM is slower with that idea. At sfc, troughing settles over scntrl Canada to the high Plains. Return flow ahead of the trough and thermal ridge should result in high temps warming into the 40s. Now looks like there will be some mid- high clouds around but even mixing to 900mb would support highs well into the 40s and even around 50F depending on how much sunshine is realized. Blend of latest models and NAEFS/ECMWF ensembles point to lowering heights and cooler air gradually working back over the region by middle of next week. Could be some light lake effect for NW flow areas. Details in how long this cold air persists is uncertain though. Unlike yesterday there is no sign from main models of any kind of strong storm system. && .AVIATION...(For the 00Z TAFS through 00Z Friday evening) Issued at 717 PM EST THU NOV 23 2017 VFR conditions will give way to MVFR conditions on Fri afternoon with a lowering of ceilings and areas of rain developing ahead of an approaching cold front from the west. LLWS is expected to develop late this evening and continue into Fri morning as a low- level wind max noses in from the west. && .MARINE...(For the 4 PM Lake Superior forecast issuance) Issued at 406 PM EST THU NOV 23 2017 Westerly winds of 15 to 25 knots will back to the south late tonight into Friday at 20 to 30 knots with gale force gusts to 35 knots expected. So a gale warning remains in effect from late tonight into Friday afternoon for most of Lake Superior. On the back side of the strong low pressure system additional gales of 35 to 40 knots are possible on colder northwest flow into the area. Winds are expected to remain in the 20 to 30 knot range through at least mid weak. && .MQT WATCHES/WARNINGS/ADVISORIES... Upper Michigan... None. Lake Superior... Gale Warning from 7 AM Friday to 5 AM EST Saturday for LSZ246>251-265>267. Gale Warning from 5 AM EST /4 AM CST/ Friday to 1 AM EST /midnight CST/ Saturday for LSZ240>245-263-264. Lake Michigan... Gale Warning from 4 AM to 4 PM EST Friday for LMZ221-248-250. && $$ SHORT TERM...JLB LONG TERM...JLA AVIATION...Voss MARINE...JLB
Area Forecast Discussion
National Weather Service Tampa Bay Ruskin FL
657 PM EST Thu Nov 23 2017 .UPDATE (Overnight and Friday)... 00Z water vapor and H4 RAP analysis shows amplified deep layer troughing digging through the central and eastern Gulf of Mexico...with a large plume of mid/upper level subtropical moisture streaming northward over the Florida peninsula ahead of the trough axis. As the trough continues to approach the area...the weak associated surface low is coming ashore near Tampa Bay. Most of the favorable synoptic lift has actually now shifted to our east and northeast...resulting in most of the area seeing just a few lighter scattered showers. More concentrated shower activity continues to move ashore into the Fort Myers area as of 7PM...associated with WAA/lift along a lower level theta-e ridge extending across the SE Gulf of Mexico to the SW Florida coast. Latest RAP progs are for this feature to shift south with time tonight...and this should shift the better rain chances south of Fort Myers eventually as well. mentioned above...the best forcing is gone, but weak large scale synoptic forcing ahead of the trough axis along with abundant moisture will still support isolated to widely scattered showers/sprinkles...but QPF amounts will be very low. As the surface low shifts slowly southeast through the rest of the evening...good agreement that lower level winds from the north/NE across the Nature Coast will expand down into the Tampa Bay Area. This flow will support the development of lower stratus across the area...initially from Tampa Bay area northward...but eventually further south as well. This stratus will mainly be a concern for the aviation community, but will likely make for a dreary start to the daylight hours of Friday. BUFKIT profiles from the NAM/RAP and local hires models are all showing very favorable thermodynamic profiles for the stratus...and support only a slow improvement during Friday morning. Can not rule out a few isolated showers Friday morning...however...drier air will be arriving aloft...even in the morning...and this should really end this potential pretty quickly. Most NWP guidance has trended faster with the exit of shower potential during the day Friday. By afternoon...looking like fairly decent weather region-wide as the deep and even lower level moisture really becomes scoured out from W to E. Pleasant weather then dominates the forecast for the rest of the holiday weekend. && AVIATION (24/00Z THROUGH 25/00Z)... The only terminals expected to see steady shower potential through midnight will be KFMY/KRSW...although restrictions associated should not fall below MVFR. Further north toward Tampa Bay area terminals, setup seems very favorable for the development of widespread lower MVFR/IFR cigs after 04-06Z. Have gone with prevailing IFR for KTPA/KPIE/LAL after midnight, with KSRQ starting just a bit later. Less favorable setup down toward Fort Myers later tonight and kept things at MVFR. Slow improvement is expected Friday morning for all keeping restrictions in the forecast through late morning or midday. A return to prevailing VFR should occur Friday afternoon. && .Prev Discussion... /issued 204 PM EST Thu Nov 23 2017/ SHORT TERM (Tonight - Friday)... A closed upper low sits over the southern portion of the Hudson Bay with deep troughing extending south along the east coast into the central Gulf of Mexico. This trough is lending support to an area of low pressure over the eastern Gulf of Mexico and associated frontal boundary that is sweeping across Florida today. The upper trough will slowly drift eastward through the period as the surface low and frontal boundary moves east of Florida on Friday. High pressure will build into the Gulf of Mexico late Friday bringing clearing conditions into the weekend. There are two separate bands of showers and storms making their way ashore along the west coast of Florida this afternoon. The northern one is located along the Nature Coast just north of Tampa Bay and the southern one is streaming onshore from Sarasota southward to Fort Myers. 60-90% POPs can be expected through the evening hours in these bands. Rain chances decrease overnight but will still remain around 30-50% through Friday afternoon. Temperatures will be slightly below average over the next couple of days as the high pressure filters in cooler air in the wake of the low pressure and frontal boundary. LONG TERM (Friday Night through Thursday)... As we enter the medium range timeframe, the pattern will begin to change as surface low pressure departs into the Atlantic Ocean, and surface high pressure builds southward. This will usher in a rather prolonged period of relatively cool and dry conditions with a series of reinforcing cold fronts and dry/stable post-frontal airmasses. For the upcoming weekend, weak surface high pressure will build southward to the northern Gulf Coast. A subtle inverted trough feature may yield increased cloudiness and a shower or two over the southern/eastern Gulf of Mexico Saturday into Sunday, but this feature will be ushered quickly southward by a secondary cold front set to move through early next week. This front will allow for the dry and seasonal weather to persist through the end of next week. Daytime highs will rise into the low to mid 70s each day with lows ranging from the upper 40s to lower 50s north to the middle 50s and lower 60s south. As usual, warmer conditions will reside along the immediate coast due to water temperatures in the upper 60s and low 70s. MARINE... An area of low pressure moves across the Nature Coast with a frontal boundary extending across the coastal waters. Showers and storms will continue through the evening hours, then diminishing in coverage by early Friday morning. High pressure builds into the Gulf of Mexico on Friday and into the weekend. Interaction between the high pressure and the front east of Florida will produce gusty winds near cautionary level late tonight through early Friday. As the high settles over northern Florida by Saturday, the winds decrease to 10 knots or less through the weekend. No other marine issues are expected. FIRE WEATHER... High rain chances and humidity levels will preclude any fire weather concerns through the period. && .Preliminary Point Temps/PoPs... TPA 63 72 59 74 / 30 30 0 0 FMY 67 77 60 78 / 70 30 10 0 GIF 62 72 56 76 / 30 30 10 0 SRQ 64 72 58 75 / 30 30 10 0 BKV 60 70 50 74 / 30 30 10 0 SPG 62 71 60 73 / 30 30 10 0 && .TBW WATCHES/WARNINGS/ADVISORIES... FL...None. Gulf waters...None. && $$ UPDATE/AVIATION/MARINE...14/Mroczka UPPER AIR...99 DECISION SUPPORT...99
Area Forecast Discussion
National Weather Service Topeka KS
450 PM CST Thu Nov 23 2017 ...AVIATION UPDATE... .SHORT TERM...(This evening through Friday) Issued at 145 PM CST Thu Nov 23 2017 Light and variable winds has not deterred the warming temperatures this afternoon. Latest high resolution guidance is trending slightly warmer than previous forecast, leading to an update of middle to upper 60s. Would not be surprised if Concordia comes close to their record high of 71 degrees today with anticipated high of 69 degrees. For these reasons and latest MOS guidance coming in for tomorrow, believe our previous forecast may have been too cool for temperatures. Frontal boundary and cooler airmass behind is showing signs of slowing as it enters north central Kansas during the mid to late afternoon. Southerly winds ahead of it increase shortly after sunrise between 15 and 20 mph with gusts up to 30 mph possible. In addition, stronger mixing aloft between the NAM, GFS, and WRF ensembles is indicative of h85 temps around 15 to 18C reaching the sfc. MOS guidance and blended models are pretty consistent in the compressional warming ahead the boundary, resulting in low to middle 70s for highs. This would be near or at the record. Please see climate information section below. The combination of the strong, shifting winds and lower RH values will also create very high fire danger conditions in the afternoon. Please see fire weather discussion for additional details. .LONG TERM...(Friday night through Thursday) Issued at 145 PM CST Thu Nov 23 2017 The weekend and much of next week will feature quiet, dry, and warm weather with large scale upper level ridging dominating the weather pattern from Friday into Monday. A sharp shortwave trough will push eastward early in the week and will drag a surface boundary through on Monday night into Tuesday. Ample mixing and a tight pressure gradient will result in a blustery day on Monday and raised winds above the blended guidance to account for this scenario. GFS soundings show winds at the top of the mixed layer pushing 40 to 50 kts, so wind advisory conditions are certainly not out of the question. This mixing will tap into a +17 to +20 C H850 warm nose, boosting temps to near record or record highs. Pushed highs to the warm end of the model blend spectrum as a result. Increasing theta-e advection and lift along the boundary may spawn some light precip on the backside of the system late Tuesday into Wednesday in SE Kansas, but this looks to be the only chance of precip in the next seven days. && .AVIATION...(For the 00Z TAFS through 00Z Friday evening) Issued at 450 PM CST Thu Nov 23 2017 VFR conditions should prevail with limited moisture in place and only some mid and high clouds passing overhead. FROPA late in the period also looks dry with no appreciable moisture advection ahead of the boundary. NAM and RAP forecast soundings do show a strengthening low level jet on the order of 35 to 40 KT with a steep nocturnal inversion developing late in the evening. Therefore will include a mention of LLWS through at least mid morning. && .FIRE WEATHER... Issued at 145 PM CST Thu Nov 23 2017 Strong south winds initiate shortly after sunrise, particularly strongest along and south of Interstate 70 at 15 to 20 mph with gusts near 30 mph. With the exception of the NAM, guidance is fairly consistent with the wind shift bisecting northeast Kansas from southwest to northeast by mid to late afternoon. Winds may briefly weaken along the boundary, otherwise they increase from the north at 15 to 20 mph in north central Kansas before weakening around sunset. Minimum RH values lower to around 30 percent given the current dewpoints and temperatures forecast, translating to very high fire danger conditions across much of northeast Kansas. && .CLIMATE... Issued at 145 PM CST Thu Nov 23 2017 Record Highs on Friday Topeka: 76 degrees set back in 1990 (Forecast: 76) Concordia: 73 degrees set back in 1990 and 2011 (Forecast: 73) -------------------------------------------------------------- Record Highs on Monday Topeka: 71 degrees set back in 1998 (Forecast: 70) Concordia: 69 degrees set back in 1933 (Forecast: 70) && .TOP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ Happy Thanksgiving! SHORT TERM...Prieto LONG TERM...Skow AVIATION...Wolters FIRE WEATHER...Prieto CLIMATE...Prieto/Skow