Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 11/21/19

Area Forecast Discussion
National Weather Service Amarillo TX
619 PM CST Wed Nov 20 2019 .AVIATION...00Z TAFS... VFR conditions will prevail at all terminals through 18z. Thereafter MVFR/IFR conditions will be possible as the next weather system moves in. Rain will be the most likely form of precipitation for KAMA. RASNPL will be possible at KDHT as this will be where the highest impacts could occur. KGUY not far behind, but for now it looks like just rain for the 18-00z time period, but will not be surprised after 00z if a change over to SN occurs at KGUY. Winds out of the southwest will begin to diminish over the next few hours, and north winds around 10kts can be expected between the 7 to 10z period. Weber && .PREV DISCUSSION... /Issued 400 PM CST Wed Nov 20 2019/ SHORT TERM...Today through Tomorrow... Satellite imagery of mid-level water vapor and 500mb heights show the closed low cutting south across the coast of California this afternoon with waves of moisture being ejected out ahead of the trough. By early afternoon, the upper level wave will cut east across southern Nevada through the morning hours Thursday. A shortwave pushed across this morning, which brought the showers through the area and kept temperatures in the upper 50s with low cloud cover. However, skies are clearing from southwest to northeast with temperatures starting to rise again. The northwest corner of the Texas Panhandle and portions of the eastern Oklahoma Panhandles are mixing down wind speeds of 25 to 30 mph with gusts up to 40 mph. If the southern Texas Panhandle is capable of clearing this afternoon and temperatures rise into the upper 60s to lower 70s, there is a potential for a severe storm or two to pop up. RAP analysis shows instability of 500-1000 J/kg of MLCAPE and 60 knot 0- 6 km effective bulk shear around 21z mainly in the far southeast Texas Panhandle. Dewpoints have the potential to rise into the 60s as the precipitation and skies clear out. An isolated strong storm or two cannot be ruled out with hail and damaging winds as the main threats. Precipitation chances will diminish after 00z with only a chance for lingering isolated storm on the far southeast Texas and Oklahoma border. Minimum temperatures will drop below freezing in the northwest half of the combined Panhandles, while the southeast half will only dip down into the upper 30s and lower 40s. Skies will continue to clear overnight, but become cloudy again tomorrow mid- morning behind a cold front that will have moved through by 12z. Winds will turn to the north northeast at around 10 to 15 mph. Rutt LONG TERM...Thursday afternoon through mid next week The main focus of the forecast remains on potential impacts from the storm system tomorrow night. All in all, very few changes were made to the inherited forecast as the northwest corner of our area continues to look the snowiest. The upper level jet is in the process of splitting and the aforementioned strong southern stream upper level low over southern California is reaching peak intensity this afternoon and will soon begin to fill and weaken. This upr low will speed up and eventually cross Colorado and Kansas tomorrow night and Fri, briefly re-intensify, and then get ingested back into the Polar jet over the ern CONUS this weekend. The big question for Panhandles residents is where exactly does this low re-intensify and how quickly does that happen. If the models are a little off on this difficult to model process, we could be in for a more dynamic situation with higher precip amounts (and therefore snow totals). While an earlier and further west intensification is possible, it does not look like the most likely scenario at this time, and have gone with a model consensus forecast. Unlike many snow events around these parts, snow banding doesn`t look as likely this go around. The snow that falls will likely accumulate in a few hours via a transient wave of briefly very heavy snow. For this reason, current thinking is that amounts will remain predominately in the 1-4" range, though most of it will fall in a small time window from roughly 5PM - midnight tomorrow. Previous thinking remains similar with the best accumulation chances north and west of a Dalhart to Guymon line, mixed precip between this line and US 60, and predominately rain south and east of the US Hwy 60 corridor. Slight deviations in temperature will shift this line, but current thinking is that impacts to Amarillo should be minimal. After a chilly Friday, a nice weekend rebound is in store. Uncertainty is above normal next week as models bounce all over the place between dry weather up to the possibility for a significant system in the High Plains. Simpson && .PRELIMINARY POINT TEMPS/POPS... Amarillo TX 36 49 31 45 30 / 0 40 80 10 0 Beaver OK 33 48 27 42 22 / 10 30 70 20 0 Boise City OK 28 38 25 42 24 / 5 50 80 5 0 Borger TX 37 49 32 45 29 / 0 40 80 10 0 Boys Ranch TX 35 49 30 47 28 / 0 50 90 10 0 Canyon TX 36 51 31 46 30 / 0 50 80 10 0 Clarendon TX 40 52 35 45 29 / 10 40 80 10 0 Dalhart TX 30 43 26 45 23 / 5 50 80 5 0 Guymon OK 31 45 27 42 22 / 5 40 80 5 0 Hereford TX 36 52 32 49 30 / 0 50 80 10 0 Lipscomb TX 36 51 29 43 26 / 10 30 70 10 0 Pampa TX 36 49 31 42 28 / 5 40 80 10 0 Shamrock TX 39 54 33 46 27 / 30 30 60 10 0 Wellington TX 41 55 35 47 27 / 30 30 60 10 0 && .AMA Watches/Warnings/Advisories... TX...None. OK...None. && $$ 89/99
Area Forecast Discussion
National Weather Service Austin/San Antonio TX
850 PM CST Wed Nov 20 2019 .UPDATE... Main change was to bump up overnight lows by a degree or two and to adjust PoPs based on radar trends and the evening high resolution models. Cloud cover has spread over much of the area with the southwest flow aloft and this should act to keep temperatures mild overnight. Precipitation wise there are some isolated storms to the southeast of San Angelo which should remain to the north and west of our Hill Country counties. Lightning and Satellite data (DFX will be down overnight, but techs are expected at the site early Thursday AM to fix the radar) do show one isolated thunderstorm approaching the Rio Grande just to the southwest of Del Rio. The lighting is very sporadic with this storm and cloud top temps of -45 degrees C are comparable with the activity to the SE of San Angelo and to the NW of DFW. Because of this have adjusted the PoPs for now through midnight to reflect the chance of showers and a few isolated storms across the Rio Grande Plains. The HRRR which was showing decent coverage across the Hill Country by early tomorrow morning has trended drier over the last 3 runs, quickly dissipating anything that does make it into the Rio Grande counties. Have kept slight chance PoPs across the Hill Country and points eastward to account for an isolated shower or weak storm that makes it into these areas by morning, in addition to some streamer showers in the southerly flow at the surface. && .PREV DISCUSSION... /ISSUED 545 PM CST Wed Nov 20 2019/ AVIATION... VFR flying conditions start the forecast, then MVFR CIGs redevelop mid to late evening. Stronger low level jet will keep KSAT, KAUS, KSSF at MVFR while weaker jet enables KDRT to fall to IFR, possibly LIFR. Mixing rises CIGs to low end VFR in the afternoon. MVFR CIGs redevelop Thursday evening. Have mentioned VCSH at KAUS overnight into Thursday where the better chances of SHRA are. Should more breaks develop in the clouds on Thursday, then TSRA are possible due increased instability. S to SE winds 7 to 15 KTs prevail, with some gusts to 24 KTs this evening and again on Thursday. PREV DISCUSSION... /ISSUED 304 PM CST Wed Nov 20 2019/ SHORT TERM (Tonight through Thursday Night)... The latest visible satellite data shows some gradual clearing of skies ongoing for areas along and east of a Carrizo Springs to San Antonio to Austin this afternoon. Elsewhere, some convection is noted to our west across the Big Bend region of Texas. Afternoon temperatures are in the 70s and 80s across south central Texas. The main concern for this evening will be monitoring for the possibility of some isolated thunderstorms across the far western portion of our area, including Val Verde county. The last several HRRR runs show some convection moving into mentioned area, as well as portions of the southern Edwards Plateau this evening. While we can`t completely rule this out, we have seen persistent cloud cover across the region and this has definitely cut down on the instability. For now, we will only maintain a very low chance (20%) for convection across this area tonight. Elsewhere, we could also see a few showers develop across the Hill Country and adjacent I-35 corridor overnight as the low-level jet increases. As for temperatures tonight, expect mild readings with most areas only dropping into the 60s overnight. We did not include any mention of fog tonight as it appears surface winds will remain a little stronger than last night. Mild temperatures are in store Thursday, with highs mainly in the 70s and lows in the 60s. With a fairly active southwest flow aloft over the region, we will also maintain a low chance for showers and storms for the Hill Country, most of the I-35 corridor and coastal plains during the daytime. Rain chances spread across most of the remainder of south central Texas Thursday night with continued southwest flow aloft. LONG TERM (Friday through Wednesday)... A cold front will move into south central Texas early Friday morning, reaching the far northern portion of the Hill country and the southern Edwards Plateau around sunrise. The cold front will make steady southward progress through the morning and afternoon hours with scattered showers and a few thunderstorms developing along the frontal boundary. Severe storms are not anticipated with this front as it appears the stronger forcing will remain across north Texas. Given the better lift will be farther north of our region, we should only see a broken line of convection develop along and north of a Kerrville to San Antonio to Karnes City line. Rainfall amounts are not overly impressive across our region, with amounts generally expected to remain in the 1/4" or less range. A quick end to precipitation chances is in store Friday evening, with only a very low chance expected along the Highway 77 corridor through the mid-evening hours. Cooler temperatures are in store Friday night, with lows dropping into the upper 30s in the Hill Country to near 50 along the Rio Grande plains. A quiet weather pattern is anticipated for the upcoming weekend as an upper level system moves east of the region, leaving stable west to northwest flow aloft over our region. We do expect another weak surge of surface high pressure to move in on Saturday, but little notable cooling is expected behind this Pacific cold front. Low-level southerly flow returns to the area by early Monday morning as the next weather system to impact our region moves through the Pacific northwest. There is some model uncertainty with respect to how quickly this system moves eastward across the Rockies into the southern U.S. plains. We do expect a cold front to move through on Tuesday, but the timing of the front remains highly uncertain. A peak at the latest 12Z ECMWF shows the timing has trended toward the slower 12Z GFS, which would bring the front through Tuesday night as opposed to Tuesday morning. For now, we will keep rain chances fairly low and confined to areas generally along and east of the I-35 corridor. Significant cooling is not anticipated behind this front and it appears overnight lows over the next 7 days will likely not drop below freezing across south central Texas. && .PRELIMINARY POINT TEMPS/POPS... Austin Camp Mabry 67 77 63 70 45 / 20 30 30 50 10 Austin Bergstrom Intl Airport 67 78 62 72 43 / 20 30 30 50 10 New Braunfels Muni Airport 66 78 62 73 45 / 20 20 20 40 10 Burnet Muni Airport 65 75 58 65 41 / 20 30 50 50 - Del Rio Intl Airport 63 80 61 76 48 / 20 - 20 0 0 Georgetown Muni Airport 67 76 60 68 42 / 20 30 40 50 10 Hondo Muni Airport 66 80 62 77 46 / 10 10 30 20 0 San Marcos Muni Airport 66 78 62 72 44 / 20 20 30 40 10 La Grange - Fayette Regional 68 79 65 75 45 / 20 30 20 50 20 San Antonio Intl Airport 67 78 64 73 47 / 10 20 20 30 - Stinson Muni Airport 67 78 64 74 48 / 10 10 20 30 - && .EWX WATCHES/WARNINGS/ADVISORIES... None. && $$ Aviation...04 Short-Term/Long-Term...Treadway
Area Forecast Discussion
National Weather Service Grand Forks ND
947 PM CST Wed Nov 20 2019 .UPDATE... Issued at 941 PM CST Wed Nov 20 2019 Headlines have expired along and west of the valley as snowfall continues to track east. Best snowfall rates currently depicted from western Polk into Clearwater and Beltrami counties where the winter weather advisory continues until 3am. Also seeing a few SFC observations in the northern valley of 2 to 5 mile visibility with FZDZ potential as saturated lower layer exists with ice nuclei aloft exiting east with the stronger forcing. Went ahead and added this to the forecast for an hour or two following the departing snow system. UPDATE Issued at 605 PM CST Wed Nov 20 2019 Narrow band of thunder developed around 430pm and is lifting northeast into colder air turning into efficient snow showers. As this area of conditional instability moves into the area north of Park Rapids towards Bemidji snowfall rates up to an inch an hour could persist for the next 2 to 4 hours. So expanded the advisory to include southern Clearwater and Hubbard. To the west snowfall has ended and let the advisory at Towner expire at 6pm. Visibilities are generally ranging from 1 to 4 miles as snowfall rates have tapered off some late this afternoon and evening. Impacts from snow covered roads are causing slow downs and both ND and MN DOT are reporting vehicle spin outs. && .SHORT TERM...(This evening through Thursday) Issued at 304 PM CST Wed Nov 20 2019 Additional snow amounts tonight will be the main issue for the period. Lead shortwave is currently pushing through the Northern Plains with low pressure to our south. There continues to be strong 700 mb frontogenesis across portions of the Devils Lake Basin into northern Red River Valley. There have been some reports of 5-6 inches over Nelson county, and the RAP has the very strong frontogenesis hanging around that region for another hour or two before shifting to the east. With snow rates of an inch per hour continuing a bit longer, and a new band developing slightly west, think there could be warning criteria snow from Nelson county into western Walsh and eastern Ramsey counties, even up into Cavalier county. Will be putting out a small winter storm warning for that area, and will monitor the band as it moves east. There are some signs that frontogenesis will weaken later tonight as it moves into northwestern MN, so will limit the eastward extent of over 6 inches of snow. The main northern branch shortwave will head eastward tonight, with some fairly strong cold air advection behind it. Snow will be tapering off, but there will be some gusty winds tonight especially over the southern Red River Valley. Have some patchy blowing snow mention but still seems that the worst winds will be south of where the heavier snow fell. Temperatures will be falling quickly too, and areas that see rain this afternoon could freeze pretty quickly overnight. Temps in the teens to 20s overnight will not rise much on Thursday, only into the low to mid 20s as cold surface high pressure settles into the region. .LONG TERM...(Thursday night through Wednesday) Issued at 304 PM CST Wed Nov 20 2019 Thursday night...Quiet and cold with northwest flow aloft and high pressure. The center of the high will be just to our south, so winds will not be completely calm. However, with a cold air mass, at least some clearing, and fresh snow, lows will drop below the 10 mark in northwestern MN with teens elsewhere. For Friday through the weekend, benign weather and seasonal temperatures will prevail with daytime highs in the 30s to lower 40s and overnight lows in the 20s. During this period, the Northern Plains remains under the influence of the northern stream of split flow regime with longwave ridging aloft prevailing over the western half of the CONUS. Northwest flow aloft and a persistent closed low over the Hudson Bay looks to track any upper level disturbances north of the international border, keeping impactful weather at bay through at least early Sunday. Warmer air builds in briefly on Sunday, yielding breezy west winds and high temperatures in the mid 30s to mid 40s. This comes with warm air advection in advance of a clipper system trekking southeast across the Canadian Prairie. At this point, there is low confidence in the exact track of this system and associated temperature fields, but probabilistic guidance suggests snow would be the most likely precipitation type associated with precipitation chances Sunday and Monday. Additionally there is good agreement that the upper low will continue to mature and stall out over northeast MB on Monday, prompting colder air to dig into the region Tuesday and dropping daytime high temperatures below the freezing mark for the middle to end of the week. && .AVIATION...(For the 00Z TAFS through 00Z Thursday evening) Issued at 605 PM CST Wed Nov 20 2019 Snow ending west to east this late this evening. IFR CIGs will give way to VFR conditions by morning. Winds will become gusting from the north at FAR overnight. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...None. MN...Winter Weather Advisory until 3 AM CST Thursday for MNZ005-006- 008-009-013>017-023-024. && $$ UPDATE...JK SHORT TERM...JR LONG TERM...BP AVIATION...JK
Area Forecast Discussion
National Weather Service Wichita KS
841 PM CST Wed Nov 20 2019 .UPDATE... Issued at 841 PM CST Wed Nov 20 2019 Mid-level dry slot has resulted in a quicker demise to the showers across all but southeast Kansas at mid-evening. While the NAM/RAP may be a bit too bullish on pocket of elevated instability, its depiction along with the HRRR of showers perhaps with thunder developing along the cold front as it moves across central Kansas and eastern Kansas seems plausible overnight. Have updated PoPs to reflect this trend after the current lull across central Kansas, though modest redeveloping PoPs will be rather progressive with the frontal movement overnight for locations west of the turnpike. KED && .SHORT TERM...(This evening through Friday) Issued at 344 PM CST Wed Nov 20 2019 Highlights: 1) Showers & a few thunderstorms 2) Cool down Thu 3) Possible wintry mix & snow Thu night - Fri Headline: Wind Advisory until 6PM Challenge: precipitation chances and type for Thu night - Fri Changes: chance and slight timing adjustments to precipitation A trough remains positioned from Hudson Bay to southern California with a wave moving across the Front Range into the Central Plains. The northern portion of the trough combines with the wave to bring a cold frontal boundary through this evening and tonight. A tightened gradient and mixing have led to gusty winds this morning and afternoon which did prompt the issuance of a Wind Advisory. There are many sites especially in southeast Kansas which are marginal and below criteria, but the advisory only goes until 6PM and may even be able to be cancelled an hour or so early. Showers and thunderstorms have developed with most of the storms in southwest Oklahoma into Texas. As highlighted in the previous discussion, roughly 500 J/kg of MUCAPE works its way into the central and eastern portions of Kansas this evening and tonight. Thus there is the potential for a few thunderstorms. Please see the mesoscale discussion for further details on the late afternoon and evening set up. Chances of precipitation exit by mid morning on Thursday with a break until the evening hours when another wave moves across. Cold air advection comes in behind the front dropping temperatures especially in the central and south central portions of the state by 10-20 degrees. The cooler air means a change in the precipitation type, but there is still the question of the level of moisture within the dendritic or ice crystal growth zone primarily in south central Kansas. Model soundings vary on this depth of moisture and presence within the dendritic growth zone thus it is a challenge to know which one is correct. Some adjustments were made to the probability of ice and respective precipitation type grid given the lower confidence. In central Kansas, there could be minor snowfall accumulations initially, but it is not expected to last very long with a wet ground and soil temperatures in the 50s. A reinforcing shot of cold air moves in with the next wave to keep high temperatures on Friday only around 40 degrees. Only lingering and slight chances of precipitation are anticipated to maybe take off some of the less pleasant factor. At least the winds should only be around 5 to 10 mph. .LONG TERM...(Sunday through Wednesday) Issued at 344 PM CST Wed Nov 20 2019 Highlights: 1) Warm up Sat - Mon 2) Potential system Tue - next Wed The southern portion of the mid and upper level trough is expected to move east across the Central Plains on Saturday. There will be little influence with this system as it has weakened by that point. A gradual warming trend should occur for Saturday thru Monday. Another system is anticipated to move through Tuesday and next Wednesday, but the models remain quite divergent. The GFS is quite aggressive with a wrapped up system which could certainly create travel concerns if its resolution pans out; however, the ECMWF does not show the same. It is really anyone`s guess at what will occur. Confidence is low on the current precipitation chances that are in the forecast, and changes are guaranteed for this time period. Temperatures could swing in either direction as well with the GFS ramping cold air advection for Tuesday. Stay tuned. && .AVIATION...(For the 00Z TAFS through 00Z Thursday evening) Issued at 542 PM CST Wed Nov 20 2019 IFR/MVFR cigs and vsbys in stratus/rain showers will prevail ahead of a cold front this evening/tonight. While a period of MVFR cigs may linger just behind the cold frontal passage, conditions are expected to improve to VFR late tonight into Thursday morning. Gusty south winds will become gusty north-northwest winds behind the front. A period of LLWS is expected just ahead of the front. KED && .PRELIMINARY POINT TEMPS/POPS... Wichita-KICT 43 52 31 41 / 60 0 40 20 Hutchinson 40 50 27 40 / 50 0 40 20 Newton 41 50 28 40 / 60 0 40 20 ElDorado 44 52 31 41 / 80 10 50 20 Winfield-KWLD 48 54 33 43 / 80 10 40 20 Russell 35 45 25 39 / 50 0 40 20 Great Bend 36 47 25 38 / 40 0 40 20 Salina 39 48 27 40 / 60 0 30 20 McPherson 39 48 26 39 / 50 0 40 20 Coffeyville 55 61 35 44 / 90 30 50 20 Chanute 54 57 34 43 / 90 20 40 20 Iola 53 56 33 42 / 90 20 30 20 Parsons-KPPF 55 59 35 43 / 90 30 50 20 && .ICT WATCHES/WARNINGS/ADVISORIES...None. && $$ UPDATE...KED SHORT TERM...VJP LONG TERM...VJP AVIATION...KED
Area Forecast Discussion
National Weather Service Marquette MI
651 PM EST Wed Nov 20 2019 .SHORT TERM...(This evening through Thursday) Issued at 354 PM EST WED NOV 20 2019 WV imagery and RAP analysis indicated a mid/upper level trough from north central Canada to a low over southern CA and a ridge through the Mississippi Valley. A vigorous upstream shortwave was lifting northeast from southeast CO. At the surface, a trough extended northeast from low pressure over western KS while ridging prevailed from the Ohio Valley into the central Great Lakes. Radar indicated weak reflectivities from ne Mn into western Upper Michigan, with mainly virga except over the Arrowhead. Temps over most of Upper Michigan and northwest WI have climbed to around 40 under mostly cloudy skies with weak WAA. Tonight, expect precipitation to increase overnight as WAA/isentropic lift increases ahead of the CO low and shrrtwv. Forecast soundings suggest that the warm layer will prominent enough for rain over Upper Michigan. Since temps have started out higher today and should only dip into the mid 30s when the rain starts, icing is not expected. However, some locally icy spots may be possible if temps drop off farther in some isold locations. Thursday, as the trough slides east of the area early, CAA with quickly falling temps will change the rain over to snow in the west around 12Z. Strong 850-700 mb fgen/deformation will support a brief period of heavier snow over the west. The synoptic support combined with strong northerly winds and 850 mb temps dropping (from -3C to - 6C in the morning to -10C in the afternoon) will also result in lake and terrain enhancement. Although QPF values to around 0.40- 0.50 inch are expected, low SLR values at or below 10/1 should keep overall accumulations in the 3 to 5 inch range from IWD to P59 and into Baraga county.. As the rain changes to snow over the rest of the area in the afternoon, smaller snow amounts of around an inch will be possible over Marquette and Iron counties. .LONG TERM...(Thursday night through Wednesday) Issued at 341 PM EST WED NOV 20 2019 Lingering lake-effect snow Thursday night into Friday morning will taper off from west to east as large-scale subsidence increases with surface ridging working into the region. This will start a period of quieter weather for Upper Michigan. Outside of a few small chances for some wintry precipitation on Sunday, the weather is expected to remain relatively quiet. Daytime highs will be close to normal, in the 30s, with overnight lows falling into the 20s. Overall, nothing out of the ordinary for this time of year. As mentioned in previous discussions, model solutions continue to struggle with the early/middle parts of next week. Unfortunately, this time period also overlaps with a busy Thanksgiving Holiday travel week. Given we`re still looking 5-7 days out at this point, there is plenty of change that will occur within the forecast as we get closer and the details become refined. Therefore, we encourage everyone to stay updated on the latest forecast as we continue to get closer. Now, onto what we know...there will be two different waves that impact the Upper Great Lakes early/middle next week. The first wave looks to impact the region Monday/Tuesday, but looks much weaker, compared to the second wave. Right now have opted to leave NBM PoPs in for the Monday/Tuesday time frame, which shows a chance for widespread snow (esp. by Tuesday). However, with this first wave digging south from Canada, it may be difficult to get decent moisture our way. Therefore, it is possible the forecast for early next week could trend drier. This first wave of energy does look to remain just north of the border in Canada, and could lead to further amplification of the secondary, stronger wave expected to lift northeast from the Plains Tuesday night/Wednesday. This secondary wave will have the potential to bring with it some better moisture from the Gulf of Mexico, depending on where the system tracks. That being said, there are major differences between model solutions that far out. To highlight just how much uncertainty there is with this secondary wave, below are a few scenarios that *could* play out based on current model guidance. - The GFS paints by far the worst-case scenario for the Upper Peninsula, with the main surface low deepening as it lifts across central Wisconsin and eastern Upper Michigan. This would favor the *potential* for system snow across the west transiting over to rain across the east, then transitioning over to all snow on the backside of the system as it exits. This storm track would favor lake- enhancement precipitation off of Lake Superior for some spots. The track and strength of this surface low would also favor strong winds over Lake Superior, which would favor higher waves and the potential for some lakeshore flooding concerns. Again, this appears to be the worst-case scenario when taking a look at the suite of medium-range deterministic guidance. - The Canadian is a bit slower with the wave and thus further south, and far weaker with the overall magnitude of deepening the surface low undergoes. This solution still favors some of eastern Upper Michigan being clipped by some snow, but overall colder air wrapping around favoring some light lake-effect precipitation across the west and wrapping in behind the departing low. - The ECMWF is even slower and further south compared to the GFS and Canadian, with no system precipitation making it this far north. In fact, the only precipitation looks to be primarily lake-driven, with lake-effect snow in the Lake Superior snowbelts. Ensembles means tend to support the surface low tracking somewhere across the Upper Great Lakes, with the mean surface fields bringing the low pressure center across central or eastern parts of Upper Michigan. Based on current model trends continuing to jump around in their solutions, the ensemble approach seems to be best in this case so didn`t make any changes to the NBM PoPs for Tuesday night/Wednesday. Of course, nothing is set in stone, but as you can see from the scenarios described above, there is still a lot of room for changes in the forecast. This applies not only to the Upper Peninsula, but the region in general. Will definitely need to keep an eye of model trends as we progress through the weekend into early next week to get a better handle on if there will be any potential for the mid-week storm system to impact Thanksgiving holiday travel. && .AVIATION...(For the 00Z TAFS through 00Z Thursday evening) Issued at 651 PM EST WED NOV 20 2019 As low pres organizing over the Plains tonight lifts ne toward the Great Lakes, expect deteriorating conditions overnight at KIWD/KCMX/KSAW as rain spreads into the area. VFR conditions or high MVFR cigs this evening will fall to LIFR late tonight at all terminals. During Thu morning, conditions will remain LIFR at all terminals as rain changes to snow by mid morning at KIWD/KCMX and mixes with snow at KSAW late morning/early aftn. NNW winds will become gusty to 20-30kt during the day. In the aftn, expect improvement to MVFR at KIWD/KSAW and to IFR at KCMX. && .MARINE...(For the 4 PM Lake Superior forecast issuance) Issued at 354 PM EST WED NOV 20 2019 Winds will back from the SW to SE tonight as a low approached Lake Superior from the Central Plains. As the low moves east of the lake on Thursday morning, winds back to the N-NW increasing in speed as the pressure falls and the gradient increases. By Thursday afternoon winds across all of the lake will be N to NW with gusts up to 40 knots. A gale watch remained in effect across the eastern half of Lake Superior starting Thursday afternoon through late Thursday night. Waves are expected to build up to 13 feet across eastern Lake Superior Thursday night. Winds will relax to around 20 knots by Friday afternoon before increasing from the W up to 30 knots Friday night into Saturday morning as a trough approaches the lake from the NW in Canada. Winds will then relax below 20 knots Saturday afternoon through Tuesday morning. There is a chance for another low pressure system to develop and cross Lake Superior Wednesday evening through Thursday, but strength and track of the low remain uncertain. && .MQT WATCHES/WARNINGS/ADVISORIES... Upper Michigan... Winter Weather Advisory from 7 AM EST /6 AM CST/ to 7 PM EST /6 PM CST/ Thursday for MIZ001>004-009-084. Lake Superior... Gale Watch from Thursday evening through late Thursday night for LSZ251-267. Gale Watch from Thursday afternoon through late Thursday night for LSZ249-250-266. Gale Watch from Thursday afternoon through late Thursday night for LSZ244-245-248-264-265. Lake Michigan... None. && $$ SHORT TERM...JLB LONG TERM...Ritzman AVIATION...Rolfson MARINE...JLB
For frequently asked questions about the Area Forecast Discussion
Area Forecast Discussion
National Weather Service Tulsa OK
851 PM CST Wed Nov 20 2019 ...UPDATE... .DISCUSSION... Progressive upper wave is currently pushing into western/central OK, with showers shifting quickly east across the region this evening. Based on radar trends and recent HRRR runs, have lowered PoPs from late evening through most of the remainder of the night. Could see some redevelopment late tonight or early Thursday morning along the cold front as it enters northeast OK. && .PRELIMINARY POINT TEMPS/POPS... TUL 60 63 37 45 / 80 40 80 50 FSM 61 67 47 53 / 40 80 100 80 MLC 64 69 40 48 / 50 80 100 70 BVO 54 58 35 44 / 90 30 70 40 FYV 60 67 40 47 / 60 80 100 70 BYV 58 68 39 47 / 50 70 100 70 MKO 62 67 39 46 / 60 70 90 60 MIO 58 63 35 43 / 80 40 70 40 F10 62 67 38 45 / 60 70 90 60 HHW 64 69 48 52 / 40 80 100 90 && .TSA WATCHES/WARNINGS/ADVISORIES... OK...None. AR...None. && $$ SHORT TERM...18