Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 11/27/19


Area Forecast Discussion
National Weather Service Dodge City KS
551 PM CST Tue Nov 26 2019 ...Updated Aviation Section... .SHORT TERM...(This evening through Wednesday) Issued at 258 PM CST Tue Nov 26 2019 Basically the hrrr updates though the day have continued to maintain a very small area of our extreme west central Kansas counties with the potential for one to three inches of snow. This will coincide with the pivoting southern end of the the snow band now focused across northwest kansas over far northern Trego and perhaps parts of Scott and Lane counties. The surface low has moved from se CO this morning to immediately south of the DDC CWA with a surge of steep low level lapse rates. Even with the surge of dry air, the front overtaking the area should relegate red flag criterion of Rh too high for warning. The strongest winds should be developing by late afternoon and continuing through the evening and be focused across the south central Kansas counties, where best potential (Clark - Comanche- Barber) for high wind gusts to 60 mph will be. Gusts to 50 knots have already been recorded at Med Lodge. Any snow accumulation across northern sections of Trego and areas southwest will cause significant blowing into the early evening as the isallobaric pressure increases ramp up the wind speeds through midnight. Rapid clearing and dry air will lead to much colder temperatures tonight, likely in the low teens west - and not out of the question to see some single digits in the ark valley. .LONG TERM...(Wednesday night through Tuesday) Issued at 258 PM CST Tue Nov 26 2019 Another storm system is on the heels of our current one. The impacts should begins as early as Wednesday night as moisture and warm advection develop. There appears to be a relative wet period Thursday and into Friday. A chance for areas of rain of freezing rain could occur Wednesday night and early Thursday as the residual cold air is still in place, however with time the models warm the layer though and airmass change, with instability offering a chance for storms along with warmer temps in the 50s to 60 by Friday. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday evening) Issued at 549 PM CST Tue Nov 26 2019 As the latest storm system pulls away tonight, expect improving aviation weather as the ceiling will eventually scatter out later on tonight (particularly in the 06-10Z time frame early Wednesday morning). Winds will also be weakening during this time frame as well. In the meantime, through 06Z, MVFR flight category is expected to persist at GCK, DDC, and HYS (with HYS experiencing some intermittent IFR closer to the backside of the storm, along with light snow). In between storm systems, Wednesday`s aviation weather looks tranquil. && .PRELIMINARY POINT TEMPS/POPS... DDC 21 42 29 40 / 10 0 70 80 GCK 16 41 28 41 / 20 0 60 70 EHA 18 43 28 43 / 0 0 70 50 LBL 18 43 27 41 / 0 0 80 70 HYS 21 38 25 38 / 70 0 50 80 P28 26 46 30 41 / 0 0 70 90 && .DDC WATCHES/WARNINGS/ADVISORIES... High Wind Warning until 9 PM CST this evening for KSZ063-064- 074>078-080-084>090. Winter Weather Advisory until 9 PM CST this evening for KSZ030- 031-043>045. && $$ SHORT TERM...Russell LONG TERM...Russell AVIATION...Umscheid
Area Forecast Discussion
National Weather Service Chicago/Romeoville, IL
737 PM CST Tue Nov 26 2019 .UPDATE... 737 PM CST Evening Update... Only minor change to going forecast was to add isolated thunder for this evening, as a few embedded cells have exhibited lightning across parts of eastern CWA and southern Lake Michigan early this evening. Expect this to continue to be the case through the evening, as RAP mesoanalysis indicates weak 100-300 J/kg of MUCAPE currently in place, and instability will only increase with continued warm/moist advection tonight. High-res CAM guidance suggests additional waves of showers/embedded thunderstorms will continue to spread northeast across the forecast area, with an increase in coverage and low-topped thunder potential likely from 11 pm/midnight onward as warm sector advances northward ahead of deepening surface low pressure tracking to our northwest through early Wednesday morning. Previous discussion of instability trends, wind fields, long hodographs and marginal isolated severe threat remain valid for overnight. Going forecast otherwise in great shape, and no changes made except for adding the aforementioned evening thunder. Ratzer && .SHORT TERM... 238 PM CST Through Wednesday night... Our potent storm system is taking shape early this afternoon with the core shortwave beginning to eject out across western Kansas. Associated strong upper jet divergence is facilitating pressure falls eastward across the Central Great Plains, and these pressure falls will roughly telegraph the location of the surface low into the evening hours as it tracks northeastward towards central Iowa. Light shower activity continues to develop across the region as low- level warm advection is really beginning to crank upstairs. This activity will remain light through the afternoon hours with perhaps a local minimum in activity south of I-80. As we work into the evening hours, however, the addition of increasing support from an incoming upper-jet should allow the slug of rain currently across Arkansas and southeastern Missouri to spread into our region. Afternoon model guidance continues to support the potential for a sliver of modest elevated instability to develop through the evening hours in the expanding warm sector south and east of the surface low. Forecast soundings show a rather limited potential for truly surface-based inflow, but kinematic profiles depict extremely strong wind fields immediately off the surface. The attendant robust large scale forcing for ascent ahead of this system may support the development of a broken line of low-topped convection, which could attempt to push into the southwestern portions of the CWA after about 11 PM. Given the aforementioned kinematics in place and already fast forward storm motions, it won`t take much to translate some 50 to 60 mph wind gusts to surface if this convective line is is deep enough. It continues to look like any linear convection would begin to outpace what little surface-based instability there is after 3-4 AM as it tracks towards the Chicago area and would overall expect a decrease in storm intensity/depth as a result. Finally, as was alluded to in the overnight discussion, in the face of such strong and stretched-out wind fields, we can`t completely discount the potential for a brief QLCS tornado spin-up given the presence of line-orthogonal deep layer shear vectors which should help keep convective updrafts propped up against any surging outflow. The main story with this system, however, continues to be on the very strong wind potential into Wednesday. We have upgraded the High Wind Watch to a High Wind Warning for all of northeast Illinois and northwest Indiana with the potential for widespread wind gusts well into the 50 mph range, occasionally to 60 mph. Still some questions about how deeply we can mix in the developing cold advection regime on Wednesday morning/afternoon, but there is enough of a signal in the model guidance to support the wind headline upgrade. The window for highest gusts will be the mid-late morning hours on Wednesday and through the mid-afternoon before things gradually abate into the evening hours. Low precipitation chances will linger for those north of I-80 into the mid-afternoon hours on Wednesday as temperatures fall into the 30s with a strong non-diurnal temperature trend. It continues to look like cloud depths will diminish quickly enough to minimize the potential for any wintry precipitation as surface temperatures fall below freezing Wednesday evening. Carlaw && .LONG TERM... 238 PM CST Thursday through Tuesday... Thanksgiving day continues to look fairly benign after the active weather period on Wednesday. Light winds will prevail although cloud cover will likely be prevalent holding high temperatures down in the mid to upper 30s area-wide. The next lead shortwave disturbance--caught up in the fast southwesterly mid-level flow spread across the nation`s midsection--now looks to wash out west of our region Thursday afternoon and evening, thus limiting the potential for additional precipitation during this period. The next strong storm system is currently dropping in towards the Pacific Northwest and California coastline, will finally spread east across the Plains towards the end of the week and weekend. As is typical with these deep upper-level systems, we`ve noted an incremental slowing trend in today`s guidance, and have begun to pare PoPs back a bit, holding them back until later in the day on Friday. This system`s current track once again places us more on the warm side, likely greatly limiting the wintry weather aspect although some rain and snow will be possible mainly north of I-80, but no accumulations are anticipated at this time. Could see more in the way of light snow towards the end of the weekend and Sunday night on the backside of this system as the main upper low begins to pivot in overhead. Carlaw && .AVIATION... For the 00Z TAFs... * Ceilings quickly deteriorating to IFR early this evening and possibly LIFR late this evening and overnight. * Showers and drizzle this evening through early Wednesday morning. * Potential for occasional lightning strikes and higher tops early this evening, with higher chances for thunderstorms late tonight. * Southwest to west winds gusting to 45 to 50 kt on Wednesday. Active period expected with a high likelihood for impactful weather this evening through Wednesday. Latest radar imagery depicting scattered rain lifting across parts of northern IL and northwest IN. Waves of rain are expected this evening through early Wednesday morning and although may only reach moderate intensity, will likely see vis periodically fall to around 2sm. Continue to monitor thunder potential this evening through early Wednesday morning, with even some thunder and higher tops noted just to the south of the terminals and more recently to the north. The potential for an occasional lightning strike and higher tops remains this evening given increasing instability aloft, and so have included a VCTS for a few hours this evening. This potential should lower later this evening, but return later tonight as a line of storms is expected to swing across the terminals. With the passage of these storms, precip chances lower through the morning, though some light rain showers may be possible for a time through midday Wednesday. Ceilings are on the way down at this time, with low end MVFR likely here in the very near term, and then with IFR ceilings becoming more likely soon after. IFR and possibly LIFR ceilings then likely through early Wednesday, but will quickly lift with the arrival of the storms. VFR ceilings then expected for a few hour window Wednesday morning, but with MVFR ceilings then returning for the remainder of the forecast period. Varying winds expected through the period, with easterly winds becoming southeast this evening, and then southwest and west Wednesday. Rather strong gusts approaching 50 kt still expected during the day Wednesday, with the highest gusts expected from mid/late morning through mid afternoon. Rodriguez && .MARINE... We have converted the Storm Watch to a Storm Warning for the nearshore waters of Lake Michigan. Southeast to south winds to 30 kt tonight will become southwest and eventually westerly Wednesday morning and through the afternoon hours as they increase in speed. Storm force wind gusts to 50 kt are anticipated on Wednesday. While winds will remain gusty, they will subside markedly Wednesday evening and overnight as high pressure quickly begins to build in from the west. Carlaw && .LOT WATCHES/WARNINGS/ADVISORIES... IL...High Wind Warning...ILZ019-ILZ021-ILZ023-ILZ032-ILZ033- ILZ039...6 AM Wednesday to 6 PM Wednesday. High Wind Warning...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010- ILZ011-ILZ012-ILZ013-ILZ014-ILZ020-ILZ022...9 AM Wednesday to 6 PM Wednesday. IN...High Wind Warning...INZ001-INZ002...9 AM Wednesday to 6 PM Wednesday. Lakeshore Flood Advisory...INZ002...noon Wednesday to 6 AM Thursday. High Wind Warning...INZ010-INZ011-INZ019...6 AM Wednesday to 6 PM Wednesday. LM...Small Craft Advisory...IL nearshore waters until 6 AM Wednesday. Storm Warning...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-LMZ745...6 AM Wednesday to 10 PM Wednesday. Small Craft Advisory...IN nearshore waters until 6 AM Wednesday. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSCHICAGO WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion...UPDATED
National Weather Service Los Angeles/Oxnard CA
405 PM PST Tue Nov 26 2019 updated aviation discussion .SYNOPSIS...26/100 PM. Today will be the last day of cool, pleasant weather before a couple cold storm systems arrive. An upper level trough of low pressure arrives late tonight bringing rain, cold temperatures, and mountain snow Wednesday and Thursday. Another system could bring additional rain on Sunday through early next week. && .SHORT TERM (TDY-FRI)...26/129 PM. Very cold upper trough continues to drop south along the west coast today with impressive deepening of the surface low off the coast of Oregon. The forecast remains more or less on track plus or minus a few hours on the timing. The cold front is going to zip through the forecast area at a rapid clip later tonight into Wednesday morning, likely confining the period of heavier rain to about 3 hours. There will also be some gusty south to southwest winds during that peak time possibly even advisory level for a few hours across the coast and valleys and up to 50-60 mph in the mountains. Rainfall rates and amounts with the front may be the highest of the entire event as we have the best combo of strong upslope flow, dynamics, and moisture with precipitable waters around 1". Instability isn`t great with the front but can`t rule out a clap of thunder or two. Latest HRRR going pretty crazy with hourly rates close to an inch in SB County with the front. This seems a bit high but it`s not totally out of the realm of possibility. More likely peak rates are around a half inch with some isolated .75/hr in the heavier cells. Minor flows are likely but much less confident in impactful flows. Will continue to monitor the storm development and high res model output but for now will hold off issuing a burn area flash flood watch. Snow levels will be a little tricky tonight. Warmer air with front will clash with pre-existing cold air at lower levels so there may be a brief period of lower elevation snow (4000-5000 feet) with minimal accumulations before the warmer air kicks up the snow levels to 6000-7000 feet later on. The front is expected to exit LA County just before noon Wednesday followed by some stiff westerly breezes and maybe even some sunshine before a secondary impulse come in Wednesday night into Thursday morning. This one is much colder but with about half the PW with the front. Individual cells will be moving slower as steering winds decrease with the approaching low but air mass will be more unstable due to the much colder air aloft. Precip will be more showery but still potentially quite heavy with graupel or small hail likely in many areas. Snow levels will fall to around 3000 feet during this time with some light snow down to as low as 2500 in heavier cells. Antelope Valley foothills will likely see a few inches of snow and possibly even a dusting down to the valley floor. Showers with possible thunderstorms will continue through Thanksgiving evening before decreasing in areal coverage and intensity Thursday night into Friday. Most areas should see some sunshine Friday but temps still mostly in the 50s at lower elevations. .LONG TERM (SAT-TUE)...26/143 PM. Interesting pattern for the weekend into early next week. Weak ridging will develop over California Saturday, however the next system isn`t far offshore and it`s tapping into a long fetch of moisture across the Pacific. The models have been struggling with the interaction between the trough offshore and the ridge but the trends appear to be favoring a return of wet weather to at least SLO/SB Counties by Saturday afternoon. The GFS is weaker with the ridge and thus allows the precip to advance farther east into Ventura and possibly even LA Counties. PW`s are quite high, almost 1.5" just off the coast with 30-40kt southwest flow at 850 mb. So this could prove to be a significant rain maker for the western part of our forecast area. It`s much warmer given the subtropical source and weak ridging aloft so this will not bring additional snow to the area. Main questions are how far east will the precip get and when and we`ll likely next another couple days to sort that out. For now pops have been increased area-wide but especially across SLO/SB Counties with rain likely many areas Sat and Sun. The GFS pulls back the precip early next week as the moisture axis shifts west but this could easily change so will keep pops in the forecast through Tuesday. && .AVIATION...27/0003Z. At 2330Z, there was no marine inversion at KLAX. Overall, moderate confidence in 00Z TAF package. High confidence in CAVU conditions for all sites through this evening with some scattered smoke possible around KSBA (due to Cave Fire). For tonight and Wednesday morning, high confidence in rain as cold front sweeps through. Also high confidence in numerous showers Wednesday afternoon. However, only moderate confidence in timing of rain and associated flight category changes. There is a slight chance of thunderstorms across the Central Coast after 12Z then after 15Z south of Point Conception. KLAX...Overall, moderate confidence in 00Z TAF. High confidence in CAVU conditions through this evening. For tonight and Wednesday morning, high confidence in light to moderate rain thru Wednesday morning, and showers Wednesday afternoon and evening, but only moderate confidence in rain timing (+/- 2 hours of current forecasts) and associated flight category changes. There is a slight chance of TSTMs after 15Z. Moderate confidence in gusty southeast winds about 15Z-19Z. KBUR...Overall, moderate confidence in 00Z TAF. High confidence in CAVU conditions through this evening. For tonight and Wednesday morning, high confidence in light to moderate rain, and for showers Wednesday afternoon, but only moderate confidence in rain timing (+/- 2 hours of current forecasts) and associated flight category changes. There is a slight chance of TSTMs after 15Z. && .MARINE...26/204 PM. For the Outer Waters, moderate to high confidence in current forecast. High confidence in a combination of Small Craft Advisory (SCA) level winds and seas continuing through Thursday. On Friday, there is a 50% chance of SCA level winds across PZZ676. For Saturday and Sunday, high confidence in SCA level winds with a 40% chance of Gale force gusts. For the Inner Waters north of Point Sal, high confidence in current forecast. High confidence in combination of SCA level winds and seas continuing through Thursday. On Saturday and Sunday, high confidence in SCA level winds with a 30% chance of Gale force gusts. For the Inner Waters south of Point Conception, moderate to high confidence in current forecast. High confidence in SCA level southeasterly winds on Wednesday as cold front sweeps through. For Thursday and Friday, high confidence in winds and seas remaining below SCA levels. On Saturday and Sunday, there is a 60% chance of SCA level southeasterly winds across the Santa Barbara Channel. && .BEACHES...26/204 PM. A HIGH SURF ADVISORY remains in effect for the Central Coast through Wednesday night as a large northwest swell will move into the waters. Surf heights will build to 10-15 feet tonight and Wednesday. For the coasts of Ventura and Los Angeles counties, a BEACH HAZARDS STATEMENT will remain in effect through Wednesday afternoon due to elevated surf (3-6 FT) and strong and dangerous rip currents. && .LOX WATCHES/WARNINGS/ADVISORIES... CA...High Surf Advisory in effect until 3 AM PST Thursday for zones 34-35. (See LAXCFWLOX). Beach Hazards Statement in effect through Wednesday afternoon for zones 40-41. (See LAXCFWLOX). Winter Storm Warning in effect from 4 AM Wednesday to 4 AM PST Friday for zones 52>54. (See LAXWSWLOX). PZ...Small Craft Advisory in effect until 3 PM PST Wednesday for zones 645-670-673-676. (See LAXMWWLOX). Small Craft Advisory in effect from 3 AM to 9 AM PST Wednesday for zone 650. (See LAXMWWLOX). Small Craft Advisory in effect from 3 AM to 3 PM PST Wednesday for zone 655. (See LAXMWWLOX). && .HAZARD POTENTIAL OUTLOOK (FRI-TUE). Cold temperatures are likely Friday and Saturday mornings with widespread frost or freeze conditions possible across the interior, possibly extending into some coastal valley locations. Periods of heavy rain possible across SLO/SB Counties over the weekend. && $$ PUBLIC...MW AVIATION...RAT/Sirard MARINE...RAT BEACHES...RAT SYNOPSIS...Stewart weather.gov/losangeles
Area Forecast Discussion
National Weather Service Memphis TN
832 PM CST Tue Nov 26 2019 .UPDATE... First round of convection continues to stream northeastward along and east of the Mississippi River. The HRRR shows a second round of convection occurring right along the cold front as it pushes into the area around 4-5Z. The best instability of the night will occur just ahead of the front thus can`t say severe threat is over behind this first round of activity. Will hold onto the Tornado Watch for now to see what happens as the front gets closer. Forecast is on track for now, but will need to update later to clean up evening wording and make some minor tweaks to temperatures. KRM && .DISCUSSION... /issued 306 PM CST Tue Nov 26 2019/ Warm advection rain showers and isolated thunder spread across much of the Midsouth this afternoon. Increasing isentropic lift will allow increasing rain chances through the rest of the day. Temperature readings are currently sitting in the upper 50`s to low 60`s with southerly winds 10-15mph and gusts near 25mph. As the surface pressure gradient tightens ahead of an approaching frontal boundary, surface winds will continue to increase. Therefore, a Wind Advisory will be in effect from 4 PM through 6 AM tomorrow morning for the majority of the Midsouth. An Enhanced Risk for severe weather remains in effect for the western portion of the CWA with a slight and marginal risk elsewhere. Winds look to still be the primary threat due to a strengthening LLJ and increasing shear profiles. There is an isolated tornado threat due to 0-1km SRH values 450-550 m2/s2. Rain will exit the Midsouth by Wednesday morning as high pressure builds back into the region. The majority of Wednesday will be breezy and cooler with highs in the 50`s. Warm advection rain showers will filter across the north on Thanksgiving Day as a shortwave ridge pass across the region. Long term models are in good agreement regarding an upper low in the Rockies progressing across portions of the Midwest this weekend. Similarly, another cold front will move through the Midsouth on Saturday increasing rain chances. By Sunday rain has exited the region and cooler temperatures pool into the area. The remainder of the period looks to be dry and cooler as high pressure returns. 17 && .AVIATION... Numerous SHRAs and a few TSRAs expected this evening as a cold front approaches. Expect MVFR conds with occasional IFR cigs/vsbys in heavier SHRAs. TSRA coverage has been limited so far due to the lack of instability so will continue with VCTS wording for now. Expect the main bulk of precip to start pushing east around 04z at KMEM. Additional development is expected ahead of the advancing cold front that will push through from 05z-10z followed by VFR conds. There could be a few TSRAs with this line but not confident enough to mention attm. Gusty south winds at 15-25 mph will veer west overnight and then to WNW on Wednesday before diminishing late in the day. SJM && && .MEG WATCHES/WARNINGS/ADVISORIES... AR...Wind Advisory until 6 AM CST Wednesday for Clay-Craighead- Crittenden-Cross-Greene-Lee AR-Mississippi-Phillips- Poinsett-St. Francis. MO...Wind Advisory until 6 AM CST Wednesday for Dunklin-Pemiscot. MS...Wind Advisory until 6 AM CST Wednesday for Benton MS-Coahoma- DeSoto-Marshall-Panola-Quitman-Tallahatchie-Tate-Tunica. TN...Wind Advisory until 6 AM CST Wednesday for Benton TN-Carroll- Chester-Crockett-Decatur-Dyer-Fayette-Gibson-Hardeman- Haywood-Henderson-Henry-Lake-Lauderdale-Madison-McNairy- Obion-Shelby-Tipton-Weakley. && $$
Area Forecast Discussion
National Weather Service Mount Holly NJ
928 PM EST Tue Nov 26 2019 .SYNOPSIS... As high pressure continues to move offshore, a strong area of low pressure will move out of the plains and into the Great Lakes. This storm system will begin to affect our region Wednesday afternoon as it moves into the Northeast. High pressure will then build into the region through Saturday, keeping our weather dry and tranquil. Another strong complex system is forecast to affect our region Sunday into Monday. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... High pressure located over the western North Altantic will continue to lose its influence over our weather during the night. Meanwhile, strong low pressure will move from the lower Missouri River Valley toward the Great Lakes. We are anticipating mainly high clouds overnight, with the arrival of some mid level clouds toward daybreak. The wind should be light and variable, and there may be some patchy light fog. Minimum temperatures in our region are forecast to range from the upper 30s to the middle 40s. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH THURSDAY/... Wednesday morning as the PV that is out ahead of the main stacked low exits the coast a weak surface low will form near Long Island with a warm front bisecting central NJ. Weak rain will form along and north of the warm front with the best forcing for ascent more towards central NY in association with the impressive 500 mb height falls. The best chance of rain across the area appears to be late morning into afternoon in association with the PV. Rainfall totals looks to be relatively low with the coverage being somewhat in question. Latest run of the HRRR actually has all of the precipitation forming along the warm front after it has passed central NJ. This appears to be the outlier though. Overall have kept PoPs at chance for most of the area (except the western zones) as mid-level dry air looks to surge east across the area in the afternoon hours. This means that the precipitation will likely come to a quick end Wednesday afternoon due to the dry mid-level air and weak subsidence on the back side of the wave. Wednesday afternoon into evening the main upper level low will approach from the west with the pressure gradient rapidly tightening. Latest GFS forecast soundings support wind gusts of 20 to 25 kts in the warm sector out ahead of the cold front. && .LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/... A strong low pressure system will approach the Great Lakes and Ohio Valley late this week and then weaken as another strong low wraps up off the coast Saturday into Sunday. Precipitation type is proving to be extremely challenging as the 12Z runs of the global models are suggesting a much more intense system with a coastal low developing near or off our coast. Moisture will be provided from a feed off the Gulf of Mexico early, then off the Atlantic as the continental parent low occludes and the new coastal low overtakes the show. We have placed the likely pops in the appropriate periods. P-type will remain tricky right up until the event begins with sleet, freezing rain, and a mix or rain and snow possible with the initial onset. Mostly rain south and east with snow and freezing rain possible across northern NJ and the southern Poconos of northeastern PA. It is far too early to begin discussing any snowfall totals, but considering the nature of the developing offshore low, some snow accumulations across the Poconos and northwestern NJ are possible later this weekend and into early next week. At this point, feel that the models may be a little too bullish on the system but this is complex and dynamic system that is worth watching, nonetheless. Slow improvement Monday with colder drier air overspreading the area on gusty north to northwesterly winds. Temperatures be early next week will be around 5 degrees below normal. && .AVIATION /03Z WEDNESDAY THROUGH SUNDAY/... The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY and surrounding areas. Overnight...Mainly VFR with high, and eventually mid level clouds. Some MVFR visibility restrictions are possible toward daybreak. Variable wind 6 knots or less. Wednesday...Some MVFR visibility restrictions in the morning, otherwise VFR with ceilings lowering into the 3500 to 4500 foot range. Scattered showers in the afternoon that may bring brief MVFR conditions. Variable wind 6 knots or less, becoming southwest and increasing to 8 to 12 knots with gusts around 20 knots in the afternoon. Outlook... Thursday...generally VFR conditions with strong northwest winds from 15 to 20 knots and gusts as high as 35-40 knots. A few light showers or sprinkles are possible, especially at KRDG and KABE, which may lower restrictions at times. High confidence in winds, low confidence in visibility/ceiling restrictions. Friday...VFR conditions expected with north-northwesterly winds from 5 to 10 knots and gusts to 15 knots. Medium confidence. Saturday...VFR conditions expected with northerly winds from 5 to 10 knots. Medium confidence. Sunday...VFR conditions to start the day, turning MVFR as skies turn overcast. Easterly winds turning northerly, and eventually northwesterly from 5 to 10 knots as a coastal low pressure center forms along the NJ Coast. Low confidence. && .MARINE... A light southerly wind is anticipated for tonight. Wind speeds are forecast to increase on Wednesday, with Small Craft Advisory level conditions expected in the afternoon, and gale force gusts around 35 knots possible late in the day. The increasing south to southwest wind on Wednesday should cause wave heights on our ocean waters to increase from around 2 feet in the morning, to 4 to 6 feet late in the day. Outlook... Wednesday night into Thursday...winds shifting abruptly from southwest to northwesterly Wednesday night. Gale force gusts likely through much of the day Thursday for most of the waters, thus a Gale Warning has been issued for all of the marine zones into Thursday evening. Seas remain elevated from 5 to 7 feet. Friday...SCA conditions likely through Friday morning as northwesterly winds diminish with the departure of a large low pressure system. Winds will gust from 25 to 30 knots Thursday night into Friday morning, then drop below 25 knots near or after 12Z Friday. Seas dropping from 3 to 5 feet in the morning to 2 to 4 feet in the afternoon. Saturday...generally sub-SCA conditions expected with north- northwesterly winds from 5 to 10 knots and gusts up to 15 knots. Seas from 2 to 4 feet. Sunday...generally sub-SCA conditions are expected across all zones Sunday, though gusts may near or exceed 25 knots for the southern three Atlantic zones and perhaps over the lower Delaware Bay as southwesterly winds turn northwesterly. Seas generally from 2 to 4 feet. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...None. NJ...None. DE...None. MD...None. MARINE...Gale Warning from 4 PM Wednesday to 7 PM EST Thursday for ANZ450>455. Gale Warning from midnight Wednesday night to 5 PM EST Thursday for ANZ430-431. && $$ Synopsis...Davis Near Term...Iovino Short Term...Haines Long Term...Davis Aviation...Davis/Iovino Marine...Davis/Iovino
Area Forecast Discussion
National Weather Service Pocatello ID
804 PM MST Tue Nov 26 2019 .UPDATE...Have produced a very minor update to the going forecast with respect to snowfall probabilities, coverage, and amounts for the overnight period. Area web cams across the central mountains showing evidence that some light snow is already beginning to fall early this evening. Accumulations do not appear to be much so far, but this does appear to be the early beginnings of the big event. Satellite imagery shows very well defined low centered over the coastal border of Oregon/California this evening. Deepest moisture associated with the low over Eastern Oregon shifting toward Idaho along with strengthening divergence aloft. More consistent snowfall still expected to arrive around/after midnight for most of East Idaho. Wind profiles still favor downsloping influence over the very southern portions of the Snake Plain in the populated interstate corridors. GFS however favoring a deeper southeast flow and stronger veering just off the surface which may be enough to overcome the downslope effects. HRRR trends also favor the strongest downslope conditions in the southern Snake Plain to develop mid Wednesday morning, which leaves several hours for the snow to develop. Of other concern is the HREF depictions of the potential for greater than 1"+ per hour snowfall rates across the central mountains, developing into Clark County/Monida region late tonight into Wednesday morning as well. Think that the current snowfall depictions into early Wednesday are generally on track and thus just made minor adjustments in line with latest high res model runs. All headlines remain intact for the overnight period. DMH && .PREV DISCUSSION... /issued 250 PM MST Tue Nov 26 2019/ SHORT TERM...Today through Friday. By late today into tomorrow models continue to show a significant storm system moving through the area. Mostly Southerly flow will dominate bringing moderate to heavy snow to those areas favoring Southerly flow, particularly the Southeast Highlands, the northern half of the Magic Valley, the northern half of Snake Plain near Craters of the Moon as well as the southern half of the Central mountains, Lost River range, the Lemhi/Beaverhead mountains and the western portions near Island park. All these areas are currently under a winter storm warning starting late tonight and going through Thursday morning for 8 to 12 inches of snow with locally higher mountain amounts of 12 to 18 inches. All other areas with the exception of areas near Stanley and Challis are under winter advisories as temperatures look cold enough for snow down low on Wednesday bringing valley amounts of 1 to 5 inches. The only area that may see a rain/snow mix will be along I-86 where Southerly down slope will likely bring warmer temperatures, especially by late morning into the afternoon. Also, expect breezy to moderate winds mainly in the morning tapering off in the afternoon where gusts of 25 to 35 mph are expected, especially for our southwest areas in the Southern Highlands and the Eastern Magic valley as well as the Snake River plain and ridgetops. These winds will create blowing and drifting snow. Expect hazardous driving conditions starting early tomorrow morning (Wednesday). The heavier snowfall will peak tomorrow morning to include most valley locations and then continue into the afternoon focusing on mountains. By Wednesday night into Thanksgiving day models continue to show upslope areas across the Southeast Highlands, southern Central mountains, southern Lost River range, Beaverhead mountains, and Island Park region to continue to get light to moderate snow into the afternoon and taper off by mid-afternoon. Colder air starts to move into the area by late Thursday into Friday. By Friday morning more moisture starts to move into the area from the southwest. Expect 3 to 7 inches across upslope areas in overall Southerly flow again. This time valley locations may see slightly more snow with 1 to 5 inches expected. Again, the Stanley and Challis areas will not see much snow. There is a little more model uncertainty with this system. The GFS models breaks away from other models as described above and shows the snow mainly hitting just our extreme southeast and east areas. Please use extreme caution and adjust driving times if possible. TW LONG TERM...Saturday through Tuesday. Looks to be a quieter period but will still have lingering snow showers in eastern highlands on Saturday as system exits. Some light snow may return Sunday ahead of the next system although right now looks fairly week and not a major storm. For now have at least a slight chance of snow daily through the extended but as mentioned looks to only be very light amounts daily and not significant travel impacts. Temperatures will start off very cold Saturday with a moderating trend then through Tuesday with high temperatures back to seasonal normals by Monday and Tuesday. GK AVIATION...Expecting poor flying conditions beginning tonight and continuing through Wednesday. Expect IFR to low IFR conditions at SUN after 08Z in heavy snowfall through Wednesday. Snow will not be as heavy at the other three sites but expect low enough visibilities in snow and low ceilings for MVFR to occasional IFR conditions at PIH, IDA, BYI and DIJ. Will be very likely for SUN to go below airport minimums after midnight tonight. GK && .PIH WATCHES/WARNINGS/ADVISORIES... Winter Weather Advisory from 11 PM this evening to 5 AM MST Thursday for IDZ051>056. Winter Storm Warning from 5 AM Wednesday to 5 AM MST Thursday for IDZ057-059>061. Winter Storm Warning from 11 PM this evening to 5 AM MST Thursday for IDZ066>069-073>075. Winter Weather Advisory from 5 AM Wednesday to 5 AM MST Thursday for IDZ058-062>065. && $$
Area Forecast Discussion...UPDATED
National Weather Service Shreveport LA
927 PM CST Tue Nov 26 2019 .UPDATE... The first round of convection has moved east of the forecast area as the stronger low-level warm air advection has also exited and instability has diminished. Thus, the tornado threat appears to have ended, so Tornado Watch #693 was cancelled for all of our area. Farther to the west, the next round of showers and thunderstorms are developing ahead of a cold front that is still west across Central Oklahoma. An isolated severe storms cannot be completely ruled out with this line, but it is quite progressive is moving east rapidly. The individual cells are also quite small, so any impacts should be short-lived. The latest HRRR suggests this line of storms will continue to build southwest across Texas and should make more of a southeastward movement around midnight, especially as the cold front surges into and across the area, finally exiting around 10z Wednesday morning. Overall, very few changes were made to the ongoing forecast. The biggest update was to remove the mention of severe thunderstorms. Otherwise, a few minor edits were made to the hourly temperature, dewpoint, and wind grids. Overnight low temperatures and the PoPs were left intact. CN && .PREV DISCUSSION... /issued 620 PM CST Tue Nov 26 2019/ AVIATION... For the ArkLaTex terminals still convective threat with isold tornadoes for KELD/KMLU for a few hours. Mid level trough is shifting low level winds and flaring off new cells with MOD turbulence from climb out with SW 20-50KT by 10kft and SW50-100KT for flight levels from 100-300 respectively. Storm tops in S AR and NE LA 35-40kft movg NEat40KT. Expecting fropa overnight to sweep out low level moisture and few clouds early before bcmg ovc 100 again by 21Z with next impulse in the brisk SW flow aloft. /24/ PREV DISCUSSION... /issued 255 PM CST Tue Nov 26 2019/ SHORT TERM.../Tonight through Wednesday Night/ Latest mesoanalysis showing our best instability axis stretching from the Lower Toledo Bend Reservoir northward into portions of SC AR attm. MUCAPE values range from near 2000J/KG near the Toledo Bend Dam to between 500-1000J/KG closer to the I-20 Corridor of N LA with values near 500 across SC AR. Likewise, deep layer Bulk Shear values in the 0-6km layer are on the order of magnitude of 60 to 70kts with 0-3km SRH values ranging between 250-300m2/s2. So while there is plenty of shear and the instability is trying to get there, what is missing is upward forcing and a near sfc trigger for the development of strong to severe thunderstorms. Looking at the latest upper air analysis, vigorous upper trough axis is just now entering the Central/Southern High Plains and will be racing towards the Upper/Mid Miss Valley by late tonight. Most of the dynamics in association with this trough axis will remain to our north but we remain borderline with strong to severe thunderstorms later this afternoon/this evening across our northern and northeastern most zones still possible. Been conversing with SPC throughout the day and the likelihood of severe thunderstorms is far from certain, but more of a conditional threat if storms can form in the warm sector to our northeast before we see sfc based instability begin to wane late this evening into the overnight hours. A strong cold front should race south and east overnight, entering our northwest most zones after 9 pm and through all but our southeast most zones by 3 AM Wed Morning, taking all the precipitation with it. There could be a narrow line of storms that form on the frontal boundary itself late tonight but anything that forms on the front will be sub- severe. Much cooler post frontal temperatures overnight compared to the prefrontal temperatures we saw early this morning with overnight lows ranging from near 40 north to the lower 50s southeast. Kept pops out of the forecast for Wednesday even through we should begin to see an increase in elevated cloud cover from the west during the day Wednesday as our flow aloft will remain out of the southwest. 13 LONG TERM.../Thanksgiving Day through Tuesday/ On Thanksgiving Day, the lead shortwave ahead of our next major upper trough will be transitioning NE from the Big Bend of Texas across the middle Red River Valley with a surge in Pacific moisture and a broad area of expanding showers. This convection will be primarily confined to the NW half of our region, generally along and north of a line from near Tyler, Texas to Hope, Arkansas. Farther south and east, rain chances will remain quite low with just very isolated showers possible through Thanksgiving Day. As a result, daytime temperatures will vary widely with highs near 50 degrees across our far NW zones and then ranging through the 50s south to near the I-20 corridor with lower and mid 60s south of I-20. Rain chances will continue to remain highest along and north of I-30 through Thursday night into Friday as forcing ahead of the upper trough will continue to induce showers in the increasing SW flow aloft. Meanwhile at the surface, a warm front will be returning northward from the Gulf coast during the day on Friday and provide increasing instability across much of the region with some embedded thunderstorms becoming more likely through Friday night ahead of the upper trough and associated cold front. By late Friday night into early Saturday morning, the cold front will be encroaching on our NW zones with showers and thunderstorms expanding SE along and ahead of the front. Instability ahead of the cold front will be increasing with MUCAPE values nearing 1000 J/kg and perhaps slightly higher, especially across the eastern half of the region where some daytime heating will occur prior to frontal passage. Shear profiles appear to be quite robust such that a solid line of strong to possibly severe convection is likely to develop and spread SE across the region through the day on Saturday. SPC`s Day 5 convective outlook currently has our entire region highlighted for Saturday so confidence in the threat of some severe weather does continue to increase. However, more specific details will come with better model consensus over the next few days as it relates to exact timing and severe weather mode. For now, it appears damaging winds will be the primary threat with isolated tornadoes being a lesser threat. As the cold front and convection clear the region later on Saturday night, cooler and drier air will quickly spill across the area with more seasonable conditions through early next week as we enter the month of December. 19 && .PRELIMINARY POINT TEMPS/POPS... SHV 48 63 47 60 / 50 0 20 20 MLU 52 63 44 61 / 70 0 10 10 DEQ 39 57 43 50 / 30 0 30 70 TXK 43 58 43 52 / 40 0 30 50 ELD 46 60 42 56 / 70 0 10 20 TYR 45 61 48 59 / 30 10 30 50 GGG 46 62 47 60 / 40 0 30 40 LFK 51 64 50 67 / 50 0 20 20 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...None. LA...None. OK...None. TX...None. && $$ 09/24
Area Forecast Discussion
National Weather Service Tulsa OK
756 PM CST Tue Nov 26 2019 .DISCUSSION... What an evening so far across northeast Oklahoma. Wind gusts enhanced by a band of showers, some evaporating before they hit the ground, and along a strong cold front reached 60 to 70 mph earlier this evening. Coffeyville KS had a gust to 75 mph. The HRRR seems to have picked up on the signal starting with the 23z run and onward and suggests that the high wind gust potential will depart to the northeast by 03Z. At this time, more than likely the high wind warning will be replaced by a wind advisory and will run until 06Z. A wind advisory was issued downstream into NW AR from 03Z to 12Z. The isolated storm that the HRRR was forecasting for much of the day developed near Pryor but didn`t mature until it moved into SW MO where severe and tornado warnings were later issued in that area. To top everything off, very dry air is accompanying this front, and in combination with the strong winds Red Flag conditions are spreading farther into eastern Oklahoma than earlier anticipated. It`s rare for this dry of an airmass to push this far east after dark. Further eastward expansion of the Red Flag warning is possible this evening. Lacy && .PREV DISCUSSION... /Issued 521 PM CST Tue Nov 26 2019/ AVIATION... CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM/KROG. Strong low pressure system moving across Kansas this evening will result in a period of strong west winds with gusts of 30-40 knots through about 09z. Scattered thunderstorms may impact western AR TAF sites at the beginning of the forecast period and may result in brief MVFR conditions. Otherwise VFR will prevail through the period with winds diminishing and becoming more northerly during the day Wednesday. PREV DISCUSSION... /Issued 327 PM CST Tue Nov 26 2019/ DISCUSSION... Rapidly deepening low pressure system in the Plains is causing lots of active weather across a large area this afternoon. To our north and west, a winter storm will bring several inches of snow along an axis from Nebraska through Minnesota. Surface cold front is now pushing into far western Oklahoma where dewpoints have fallen into the single digits/teens and dangerous fire weather conditions are ongoing. Very strong surface winds are occurring across western Oklahoma this afternoon with gusts in the 50-60mph range in some locations. These winds will spread into northeast Oklahoma and northwest Arkansas late this afternoon and tonight, with a wind shift to the west this evening and gusts possible in the 40-45 mph range. A line of showers and thunderstorms will gradually move out of western Arkansas late this afternoon. Wind profiles will improve tonight, but instability has been lacking to support a more organized severe threat in northwest Arkansas. The higher severe threat will be across central AR/northern LA. There will be a low potential for isolated strong storms tonight across northwest Arkansas, if storms can redevelop as the cold front moves east and interacts with the better moisture. On Wednesday, the gradient will relax, with decreasing winds and high temperatures back in the upper 40s to lower 50s. This day will be the quieter weather day ahead of the next storm system, which will begin affecting eastern Oklahoma by Wednesday night. Widespread cold rain will develop for Thanksgiving Day, with highs only in the low to mid 40s. A warm front will move back north into the area on Friday, with surface moisture rapidly returning. A squall line may develop late Friday into early Saturday morning, with the potential for severe storms across eastern Oklahoma and western Arkansas. The rest of the holiday weekend will dry out on Saturday with highs back in the 60s, with another cold front arriving by Sunday. && .PRELIMINARY POINT TEMPS/POPS... TUL 35 50 37 41 / 10 0 60 100 FSM 39 53 40 45 / 30 0 20 100 MLC 36 51 38 44 / 10 0 60 100 BVO 33 50 34 42 / 10 0 50 100 FYV 35 48 36 43 / 40 0 20 100 BYV 35 49 35 41 / 40 0 20 90 MKO 34 50 37 40 / 10 0 50 100 MIO 34 48 34 44 / 20 0 20 100 F10 36 50 37 41 / 10 0 60 100 HHW 38 53 41 48 / 20 10 50 90 && .TSA WATCHES/WARNINGS/ADVISORIES... OK...Wind Advisory until 6 AM CST Wednesday for OKZ069. Wind Advisory until midnight CST tonight for OKZ065-066-068-070- 071-073. High Wind Warning until midnight CST tonight for OKZ054>064-067. Red Flag Warning until 9 PM CST this evening for OKZ054>056- 059>061-064>066. AR...Wind Advisory until 6 AM CST Wednesday for ARZ001-002-010-011. && $$ LONG TERM....30
Area Forecast Discussion...UPDATED
National Weather Service Tucson AZ
849 PM MST Tue Nov 26 2019 .SYNOPSIS...A weather system will bring deep moisture and showers spreading up from the south Wednesday afternoon and Wednesday night. Areas of flooding possible southeast of Tucson. A strong Pacific storm will bring significant valley rain and mountain snow later Thursday into Friday. Windy conditions and much cooler temperatures are also expected. Chilly overnight lows to end the week, with warmer afternoon highs early next week. && .DISCUSSION...Sent a quick update to tweak temps this evening and POPS later Wednesday into Wednesday evening based on the latest guidance. The adjustments were upward in nature for the afternoon into the overnight hours, especially where we had significant QPF forecast where I jumped the pops solidly into the categorical range. The pop increase also included the Tucson metro area based on latest deterministic and short range ensembles. If the trend of shifting the back edge a bit further west continues, we may need to increase the pops a bit more. There is likely to be a fairly sharp edge to the precipitation on the west side Wednesday afternoon and placing that is a bit tricky. No other tweaks made at this time. && .AVIATION...Valid through 28/00Z. FEW-SCT clouds at 8k-12k ft MSL, BKN-OVC clouds AOA 20k ft MSL. Showers spreading in from the south Wednesday with SCT-BKN clouds 8k- 10k ft MSL, brief MVFR conditions possible south of KTUS. SFC wind wly to nwly at 10-18 kts this afternoon, diminishing overnight. SE-S winds 10 to 12 kts Aft 27/13Z. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER...A good chance of valley rain will be possible from Tucson south and east Wednesday afternoon, spreading across all of southeast Arizona Wednesday night into Friday with significant snow possible in the mountains. The precipitation will then come to an end from west to east late Friday night into Saturday. Strong and gusty winds will also occur late Thursday afternoon through Friday. High winds possible in the mountains and some Cochise County valleys. Dry and warmer conditions are expected Sunday into Tuesday of next week. && .PREV DISCUSSION... /issued 319 PM MST Tue Nov 26 2019/ A busy pattern this week continues. Our first low has lifted into the front range of the Rockies with the trailing cold front pushing through our area earlier this morning. The front is washing out in northern Mexico, with the HRRR showing higher dew points pushing back in from the south as early as tonight. A low off the coast of Baja is guiding much deeper moisture toward our area over the next 36 hours, with showers spreading in from the south tomorrow afternoon. Areas of heavy rain will bring some flooding concerns late Wednesday into Thursday morning. Precip amounts of 1 to 2 inches across southern Santa Cruz and the southern half of Cochise county, with isolated higher amounts possible. Snow levels should generally remain above mountain tops with this first system. The final piece of our weather puzzle this week will be a strong and cold system digging down the west coast over the next 60 hours. Showers will increase in a strong upslope warm sector ahead of the low late Thursday into Friday morning. Some clearing from the west late Friday with a few snow showers hanging on in the mountains Friday night. Snow levels will start to drift lower Thursday evening, to around 8000 feet initially. A strong cold front will push snow levels rapidly lower Friday morning, bottoming out near 5000 feet Friday night. Our best moisture and precip will correspond with snow levels near and above 7000 feet just ahead of and with the FROPA. 1 to 2 feet of snow above 7000 feet with up to 3 feet near mountain peaks. Another round of valley rain as this occurs, with possible flooding concerns in some locations. Strong winds also a concern, with windy conditions by Thursday evening. High winds in the mountains (up to 50 or 60mph) handled by the Winter Storm Watch, but we may need a High Wind Watch for some lower elevations including Cochise County. This system will push quickly into the central plains Saturday with a dry westerly flow for most of the weekend. Chilly mornings will remain, but a warming trend for daytime highs by Sunday. We could see another system by the middle of next week. && .TWC WATCHES/WARNINGS/ADVISORIES... Flash Flood Watch from Thursday morning through Friday afternoon for AZZ501>506-509>511-514-515. Winter Storm Watch from Thursday evening through Friday evening for AZZ510>514. Flash Flood Watch from Wednesday afternoon through Friday afternoon for AZZ507-508-512-513. && $$ PUBLIC...Cerniglia/Meyer AVIATION....Lader FIRE WEATHER...Lader Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson