Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 01/12/18

Area Forecast Discussion...Updated
National Weather Service Billings MT
832 PM MST Thu Jan 11 2018 .UPDATE... Not much to update. Earlier update took care of quick temperature drop over the west. Temperatures have steadied out at Livingston and do expect rising readings overnight there. Snow was filling in on the radar, but at this time, snow was rather light. Strong shortwave was entering northern Idaho, so expect snowfall to intensify over the next several hours. Adjusted PoPs up a bit as snow started a little earlier than expected at Miles City. Latest high resolution models have the bulk of the snowfall tonight, with a definite tapering off trend during the morning. This was hinted at by the GFS as well. Expect a lull early Friday, before the next round moves in late Friday afternoon into Friday evening. Will have to watch Livingston closely as the RUC pointed to higher snow amounts than existing forecast. Snow has been rather light there so far, and with expecting winds switching to the southwest with rising temperatures overnight, will leave totals alone for now. Advisories in good shape. TWH && .SHORT TERM...valid for Fri and Sat... Arctic airmass over the region today kept many places in the single digits above and below zero, while some of the foothill and mountain locations were in the balmy teens and twenties above zero. Winds have been a challenge today along the western foothills, with a baroclinic zone hugging the slopes of the mountains. Winds may turn southwest for a time late this evening and overnight at Livingston with perhaps a bit of blowing and drifting snow. Otherwise, snow will overspread the area this evening and overnight as the next system moves into the region in the form of a shortwave trough. Pacific moisture will overrun the colder air near the surface, with a surface low diving south and east into Wyoming continuing upslope flow, producing periods of accumulating snowfall. Snow looks to end across portions of the area during the day Friday, but continue through the afternoon and into the evening for areas west of a Forsyth to Broadus line as a baroclinic zone pushes south and west. When all is said and done, the western mountains could pick up 10 to 15 inches of snowfall, highest on south and west facing aspects, with significantly less amounts on north and east facing aspects. For the lower elevations, locations west of a Forsyth to Broadus line and areas north of I-90 and I-94 could see amounts of 2 to 5 inches, with locally higher amounts possible. Given winds aloft look to remain out of the southwest, locations along the southwest foothills are not expected to receive much snow. Have continued the Winter Storm Warnings for the western mountains, and expanded the Winter Weather Advisories across the rest of our Montana zones, with the exception being the southwest foothill locations. Went with Winter Weather Advisories for our far eastern areas tonight into Friday instead of a Wind Chill Advisory because we are expecting a couple inches of snow along with wind chill values down near 35 degrees below zero. The rest of the Winter Weather Advisories go into Friday evening. A mainly dry day can be expected for Saturday with shortwave ridging building over the area. A jet max moving overhead may bring some snow showers to eastern areas during the evening and night. High temperatures will range from the twenties across western foothills, to near zero degrees across the east on Friday, with thirties across the west and central zones on Saturday, with twenties across the far east. Lows will continue to be coldest east (lows below zero) and warmest west (teens to near twenty above zero). STP .LONG TERM...valid for Sun...Mon...Tue...Wed...Thu... Next clipper dropping out of Canada in amplifying flow aloft will bring our next chance of snow and next surge of colder air Sunday afternoon and night. There is time for downslope warming ahead of this 30s to lower 40s expected in our west, with gusty winds along the foothills. Backdoor front arrives in the afternoon and evening and temps should fall sharply with the wind shift to NE-E. Models have differed with the strength of the energy and magnitude of cooling, with the ECMWF being colder than the GFS, but the 18z GFS has trended colder. Have kept temps sided with the more consistent colder model, which is given further credence by the large area of snow cover in the lee of the mountains and strong high pressure dropping out of Canada. As for snowfall, could see an inch or two in central/eastern zones with mostly weak upper level forcing but a favorable dendritic layer along a low level baroclinic zone. Snow could push all the way to the foothills by late Sunday night, but this is more uncertain. Temps will drop and highs on Monday should range from the single digits in our east to maybe 30s in our west, depending on when downslope winds kick back in. The trend for the remainder of the extended period is for more zonal flow as the west coast ridge breaks down. Tuesday looks like a dry day. Could see some showers Wednesday with a Pacific shortwave. Another shortwave and lower heights expected by Thursday. Temperatures should moderate to the 30s to lower 40s in this regime, and that should begin to melt some lower elevation snow cover. Expect some gusty west winds as well, which could cause blowing/drifting snow, especially Tuesday which is the transition day from colder temps. JKL && .AVIATION... Snow will develop by this evening and continue into Friday across most of the region. Poor flight conditions will become widespread. Expect IFR or lower, and mountains will be completely obscured. Snow will become lighter on Friday afternoon with MVFR- IFR persisting. KLVM could see a period of gusty SW-W winds late tonight and early Friday, but there is uncertainty with winds along the foothills, with east winds across the lower elevations and west winds over the high terrain. JKL && .PRELIMINARY POINT TEMP/POPS... Fri Sat Sun Mon Tue Wed Thu ----------------------------------------------------------- BIL 903/007 004/038 026/038 011/025 013/037 027/041 026/041 97/S 52/O 12/S 52/S 00/B 12/J 11/B LVM 003/032 025/041 031/040 017/037 024/043 028/042 029/044 95/S 32/R 11/N 21/B 00/N 22/J 12/W HDN 905/004 903/037 019/034 006/022 005/034 021/042 026/044 95/S 42/O 12/S 51/B 00/U 02/J 11/B MLS 913/905 913/024 015/027 907/006 902/025 017/037 022/038 +5/S 13/S 14/S 30/U 00/U 01/B 11/B 4BQ 907/005 906/034 021/033 901/017 002/031 020/041 024/044 85/S 22/S 24/S 40/U 00/U 01/B 11/B BHK 915/000 915/023 013/026 913/007 910/023 012/036 021/041 85/S 13/S 25/S 20/U 00/U 01/B 11/B SHR 001/015 006/039 024/039 014/028 010/039 024/042 026/046 54/S 32/O 12/S 52/S 00/U 01/B 01/B && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...Winter Weather Advisory in effect until 11 PM MST Friday FOR ZONES 28>31-34-35-38-40>42-57-58-63. Winter Weather Advisory in effect until 11 AM MST Friday FOR ZONES 32-33-36-37. Winter Storm Warning in effect until 11 PM MST Friday FOR ZONES 67-68. WY...None. && $$
Area Forecast Discussion
National Weather Service Charleston SC
1041 PM EST Thu Jan 11 2018 ...DENSE SEA FOG LURKING ALONG THE GEORGIA AND FAR SOUTHERN SOUTH CAROLINA COAST... .SYNOPSIS... A coastal trough will shift inland through tonight. A cold front will move through Friday evening, followed by a secondary front Saturday night. Cool high pressure will settle over the area Sunday through much of next week. && .NEAR TERM /UNTIL 6 AM FRIDAY MORNING/... No major changes were made for the late evening forecast. Did nudge overnight lows up a few degrees for most areas as elevated winds and low T-Td depressions should keep conditions rather warm and humid for January. The coastal trough has pushed inland and surface dewpoints have climbed into the upper 60s for most areas. Bands of rain will continue to rotate inland across mainly the Charleston Tri- County area for the next few hours and the highest pops (up to 50%) remain clustered in this area. The risk for measurable rains has generally ended for the remainder of Southeast South Carolina and Southeast Georgia, except far interior Southeast Georgia where a few showers could still brush those areas as weak low pressure moves north. Maintained low-end mentionable pops for the next few hours to account for this. The main concern for the overnight period is centered on the potential for dense fog. Widespread sea fog has already developed across the coastal waters early this evening as upper 60 dewpoints advect over chill Atlantic waters well into the 40s. Although surface winds will remain elevated through the night, the advection of sea fog inland will bring the risk for low visibilities for much of the coast as surface winds veer to the south and increase parcel residence times over the cold shelf waters. It is unclear how far inland the sea fog will spread given the elevated winds atop the marine/boundary layer and much of this could very well transition to low-stratus. However, high resolution guidance members, including the H3R, RAP and the Time-Lagged Rapid Refresh Ensemble (NARRE-TL) have been consistent in showing very high probabilities for dense fog spreading as far inland as the I-95 corridor by daybreak. A Dense Fog Advisory may very well be needed over the coming hours for portions of the Georgia and far southern South Carolina coast. Adjusted near term pops, weather and temperatures to reflect going trends. Also expanded mention of dense fog with vsbys 1/4 mile or less into most the coastal zones. && .SHORT TERM /6 AM FRIDAY MORNING THROUGH SUNDAY/... An upper trough will lift from the northern Gulf of Mexico into the Carolinas late Friday, pushing a cold front through Friday night. Immediately ahead of the front, deep southerly flow will bring in unseasonably warm and moist air. We anticipate another day with high temperatures climbing into the low to mid 70s with surface dewpoints in the low to mid 60s. PWATs are forecast to rise to 1.6-1.7" which is around the daily climatological maximum for CHS. There continues to be fairly good model agreement on the main frontal precip band moving into our southeast GA zones during the mid afternoon, then through southern SC by early Fri evening. Although Lifted Indices and CAPEs will be marginal, we maintained a slight chance for tstms during the afternoon and evening. Much colder, drier air will shift in late Friday night into Saturday, followed by a secondary cold front Saturday evening. Highs on Saturday will be about 20 degrees cooler than Friday, then Sunday will be another 8-10 degrees cooler than Saturday. && .LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/... Quiet weather is expected to continue through the long term period, with no mentionable PoPs in the forecast. Upper troughing will persist over the eastern half of the country. Meanwhile at the surface, high pressure will largely dominate the weather pattern, although a dry cold front will quickly cross the area late Tuesday. Temperatures will be cooler than normal, especially beyond Tuesday as strong cold advection takes place. && .AVIATION /04Z FRIDAY THROUGH TUESDAY/... Primary concerns: * fog/low-stratus KCHS: A band of showers moving north across the Tri-county area should be clear of the terminal by 00Z. Will maintain VCSH through 04z to account for any additional showers that could move inland from off the Atlantic. Sea fog has developed along the Georgia and far southern South Carolina coast this evening. Some of this could get into the terminal early Friday, but guidance is consistent in keeping the higher dense fog probabilities to the south. Will show MVFR cigs developing overnight with vsbys limited to right at alternate minimums to trend. The fog/status should lift by mid-morning with VFR conditions returning. The risk for showers will increase at the end of the 00Z TAF period. KSAV: Sea fog has developed along the Georgia coast this evening and will spread inland this evening into the terminal. Current progs suggest fog could being to impact the terminal as early as 03Z with dense fog developing by 05Z. Given the consistent trends noted in the various high resolution data, will go ahead and bring prevailing dense fog with both vsbys and cigs below airfield minimums into the terminal by 05Z and keep these conditions in place through 14-15Z Friday. Conditions should rapidly improve thereafter. The risk for showers will increase at the end of the 00Z TAF period. Extended Aviation Outlook: Flight restrictions possible Fri afternoon/evening as showers and isolated thunderstorms move through. && .MARINE... Expanded the Marine Dense Fog Advisory to include Charleston Harbor. Webcams and Charleston Harbor Control report dense fog expanding in the harbor. Webcams and satellite data show dense sea fog has developed across the Georgia nearshore waters up to near Edisto Beach, SC. Have issued a marine Dense Fog Advisory for all nearshore legs through late morning Friday. Patchy sea fog will continue in the Charleston Harbor this evening with the risk for more widespread fog increasing by late evening. The advisory may very well need to be expanded to include the harbor over the coming hours. Tonight: A coastal trough will push inland as southerly winds strengthen ahead of an approaching cold front. Winds will mainly be 15 kt or less but seas continue to be high mainly due to ESE swells. Significant wave heights should remain at least 6 ft across all waters most of the night and thus Advisories will be in effect everywhere outside Charleston Harbor. By daybreak seas should subside below 6 ft for at least the nearshore GA waters. Friday through Tuesday: Gusty south winds on Friday will become westerly late Friday night behind the cold front, then northerly Saturday night into Sunday after another front drops through. Winds will remain somewhat elevated into next week as a modest gradient persists and cold air advection provides decent mixing over the waters. Small Craft Advisories continue for the Charleston nearshore waters and GA offshore waters through Saturday afternoon after which the 6 ft seas should subside. Sea fog: Very warm, moist air will flow across the cool shelf waters through Friday, likely maintaining a bank of sea fog over the nearshore waters. We kept areas of dense fog in the forecast in these areas and Dense Fog Advisories will be possible. The fog should begin to clear out by Friday evening as winds turn more offshore. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...None. SC...None. MARINE...Dense Fog Advisory until 10 AM EST Friday for AMZ330-350-352- 354. Small Craft Advisory until 7 AM EST Friday for AMZ352. Small Craft Advisory until 4 PM EST Saturday for AMZ350. Small Craft Advisory until 7 PM EST Saturday for AMZ374. Small Craft Advisory until 4 AM EST Friday for AMZ354. && $$
Area Forecast Discussion
National Weather Service State College PA
1001 PM EST Thu Jan 11 2018 .SYNOPSIS... A complex winter storm will bring rain, ice and snow to Central Pennsylvania, causing significant travel disruptions into the weekend. The mild air and heavy rain will increase the risk of ice jam and low-lying area flooding. After the brief January thaw, progressively colder air will return to the area with sharply falling temperatures and freeze- up possible on Saturday. Below average temperatures will persist into early next week. && .NEAR TERM /THROUGH FRIDAY/... The first round of rain is progressing smartly north and has reached my central zones. The HRRR shows the rain continuing to progress eastward overnight. Models are in agreement in depicting an axis of 1-2 inches over northwest 1/3 of the CWA through 12Z/7AM tomorrow. Lighter rains are expected during the day Friday with areas of fog before the next round of precipitation arrives Friday night. Temperatures will be unseasonably mild with 50-60F highs feeling very spring-like to end the week. && .SHORT TERM /FRIDAY NIGHT THROUGH SATURDAY NIGHT/... Increasingly negative tilt shortwave pivoting across the Southeast will track a more pronounced surface low from the southern Appalachians toward the northern Mid Atlantic coast. The consensus model (GFS/ECMWF/CMC/NAM) track continues to be east of the Appalachians and Blue Ridge Mountains with 12z UKMET west of the WPC preferred blend. The NAM is a bit faster than the other models. As arctic air impinges on a robust baroclinic zone, overall confidence continues to increase in a swath of moderate to heavy snow on the northwest edge of the precipitation shield across far northwest PA within zone of enhanced UVVEL and low to mid level FGEN. Upgraded to warning for Warren and McKean Counties with 6-12 inches expected. The heavy snow will be preceded by a transition from rain to wintry mix which will shift to the southeast with time. The shallow cold air will initially undercut the warm/moist air with a significant icing zone possible over parts of Central PA before changing to snow as cold air deepens through the column. Expanded winter storm watch to the Laurels and adjacent Pocono Counties given uptick in WWD deterministic forecast and overall potential for more snow/ice. Also have some concern over parts of south central PA between I-99 and I-81 which seems to be in the tightest gradient or area of max uncertainty. The 12/00Z HREF should provide valuable insight on thermal profiles and snow/ice accumulation potential with winter weather advisories likely to be issued on the next shift cycle. A very messy start to the weekend for sure, with a glaze of ice and coating of snow/sleet possible as far south as the Route 30 corridor. It will turn sharply colder Friday night into Saturday with a drastic swing from very mild temperatures to arctic cold. This may result in a rapid freeze-up of standing water/slush on untreated surfaces. Wind chills will range from around 10 below in the west to the low single digits in the Lower Susq. Valley by Sunday morning. && .LONG TERM /SUNDAY THROUGH THURSDAY/... Winter conditions for much of the extended. Cold and windy Sunday with temperatures below average everywhere. Cold for the first half of the work week. Will keep low pops for light snow across the western half of area. Next weather system later on Wednesday with a period of snow possible for much of the region. Some snow accumuations are possible with this. && .AVIATION /03Z FRIDAY THROUGH TUESDAY/... Expect aviation ceilings and visibilities to lower from west to east overnight, as rain and deep moisture overspreads Central Pennsylvania. The result will be widespread IFR/LIFR ceilings and visibilities developing in most areas overnight, and continuing through Friday. LLWS likely in all areas overnight, lasting into Friday in eastern areas. Periods of rain continue Friday along with significant flying restrictions and gusty south winds, with an eventual changeover from rain to snow from northwest to southeast during the afternoon and evening. Winds too will shift from south to northwest with the passage of a strong cold front later Friday into Friday Night. Low ceilings and reduced visibilities likely through Saturday morning. Improving weather for the weekend, though winds will continue gusty. Outlook... Sat...AM rain/low cigs poss east. AM snow/ice poss central/west. Sun...No sig wx expected. Mon...PM light snow poss west. PM low cigs poss east. Tue...Morning snow ending. Becoming VFR south and east, lingering snow showers and restrictions over the mountains. Wed...Snow showers and restrictions N and W, VFR elsewhere. Thu...VFR. && .HYDROLOGY... A mild surge in temperatures combined with 1-3 inches of rain will produce significant rises on rivers and streams with the potential for ice jams and low-lying flooding. Streamflows are currently low, but many waterways are choked with ice. The greatest risk of flooding is in the Watch area over north- central PA where snowmelt will be a contributing factor. Temperatures are expected to fall sharply below freezing by Saturday and could reinforce ice jams. && .CTP WATCHES/WARNINGS/ADVISORIES... Flood Watch through Saturday evening for PAZ004>006-010>012- 017>019-037-041-042-045-046-049>053. Winter Storm Watch from Friday evening through Saturday afternoon for PAZ042-053-058. Winter Storm Watch from Friday afternoon through Saturday afternoon for PAZ006-010>012-017-018-037-041. Winter Storm Watch from Friday evening through Saturday afternoon for PAZ024-033. Winter Storm Warning from 4 PM Friday to 4 PM EST Saturday for PAZ004-005. && $$ SYNOPSIS...La Corte/Steinbugl NEAR TERM...La Corte SHORT TERM...Steinbugl LONG TERM...Ross AVIATION...Jung/Ross HYDROLOGY...
Area Forecast Discussion
National Weather Service Duluth MN
417 PM CST Thu Jan 11 2018 .UPDATE... Issued at 414 PM CST Thu Jan 11 2018 A gravity wave induced narrow band of moderate to heavy snow has developed along the North Shore into parts of Duluth to eastern Carlton County. This band is further west than typically seen from a gravity wave and snowfall rates around an inch per hour will be possible under this band. The RAP continues to suggest drier air will move in and this band of snow should weaken then dissipate after 6 pm. && .SHORT TERM...(This evening through Friday) Issued at 151 PM CST Thu Jan 11 2018 Surface low pressure was centered near or just east of Lake Superior as of 130 pm. A well defined shortwave was seen on water vapor imagery moving north out of eastern Iowa. Area radars showed moderate to heavy snow over parts of northern Wisconsin and adjacent eastern Minnesota with more moving out of western Wisconsin and southeast Minnesota. Snowfall rates will be around an inch per hour at times. The snow also continued to diminish from the west with light snow or flurries over most of Aitkin and far western Saint Louis Counties. Most of the snow will diminish or end around 00Z Friday, except over far northern Wisconsin. Lake effect snow and a gravity wave induced band of snow should continue to produce snow along much of the South Shore, all the way west into northern Douglas County. We extended the Winter Weather Advisory for Douglas and Bayfield County through 03Z, after which time enough dry air should move in to shut down the gravity wave snow. Lake effect snow will continue all night in Iron/Ashland Counties due to northerly winds. However, the snow intensity should diminish late tonight as inversion levels lower and more dry air moves in. Additional accumulation tonight twill range from 1 to 4 inches with the higher amounts in the Gile, Montreal, and Hurley areas. Tonight will be cold with lows 25 to 30 below zero along the International Border to the single digits below zero over the South Shore toward Price/Sawyer Counties. There will be enough wind to create wind chill values from 25 below to around 40 below over much of northern Minnesota into far northwest Wisconsin. We will likely issue a Wind Chill Advisory for those areas. There may be a few wind chills below 40 below but confidence in that occurring and the need for Wind Chill Warning is low. Friday will be cold with highs in the single digits above and below zero. It should be mostly sunny with more lake clouds and light snow showers in the snowbelt along the South Shore. .LONG TERM...(Friday night through Wednesday) Issued at 151 PM CST Thu Jan 11 2018 For the long-term forecast, no major winter storm systems look to be on the horizon, but temperatures will be much colder compared to what we experienced earlier this week. The best chances of widespread snowfall will be on Sunday. Friday night through Saturday will be dry across nearly all of the Northland as surface high pressure builds across North Dakota. A very dry air mass will also be place, so expecting a very cold night over the region. Decreased overnight lows slightly to better accommodate the radiational cooling as the consensus blends were a bit too high. Lows look to drop to between -15 to -30, with the coldest temperatures over north-central Minnesota. Wind Chill Advisories will very likely be needed, with perhaps winds chills pushing warning criteria over Koochiching county. The only precipitation during this time might be some lake enhanced snow over the snowbelt of Iron county in northwest Wisconsin as low-level lapse rates remain steep and favorable northwest flow and little shear develop. The best chances for widespread light snow will return Sunday morning, continuing through Monday morning as a mid-level shortwave trough dives southeast from Manitoba and over the Northland. Pretty good large scale lift will be associated with the wave as indicated by the Thaler QG 850-300 mb omega progs. GFS/NAM model soundings indicate a fairly deep layer of saturation in the dendritic snow growth zone, but the isentropic lift within that zone looks to be minimal, so high snow fall rates should be limited. Given the amount of QPF from the models, total snow through Sunday night could range between 1 to 2 inches, with possible higher amounts along the Gogebic Range of northern Iron county due to lake enhancement. This lake enhancement over the Lake Superior snowbelt could continue through the early part of next week. One concern for this lake enhancement is that the GFS model is bringing a very favorable 1000- 850 mean flow fetch along the length-wise direction of Lake Superior, which could bring the potential for several inches of lake effect snow. However, uncertainty still exists as the ECMWF/GEM models don`t show this, so not putting much stock into the GFS solution for now, but will need to be monitored. && .AVIATION...(For the 18Z TAFS through 18Z Friday afternoon) Issued at 1138 AM CST Thu Jan 11 2018 A range of MVFR to LIFR conditions continue across the Northland as a potent surface low makes its way over Lake Superior. Conditions should gradually improve from west to east as the low exits the region this afternoon. Gusty northwest winds and light snow will maintain lower visibilities due to blowing snow through at least the middle afternoon. It`s possible that lower visibilities could linger later than what is in the TAFs due to these gusty winds but are still expected to improve by the evening hours. Ceilings could also approach MVFR or lower in some locations across the area as well. && .PRELIMINARY POINT TEMPS/POPS... DLH -13 1 -17 1 / 50 0 0 0 INL -29 -4 -28 -2 / 0 0 0 0 BRD -17 2 -22 1 / 0 0 0 0 HYR -9 6 -18 2 / 50 0 0 0 ASX -2 7 -10 4 / 60 20 0 10 && .DLH WATCHES/WARNINGS/ADVISORIES... WI...Wind Chill Advisory until noon CST Friday for WIZ001-006. Winter Weather Advisory until 6 PM CST this evening for WIZ006- 007. Winter Storm Warning until 6 PM CST this evening for WIZ008-009. Winter Storm Warning until midnight CST tonight for WIZ003-004. Winter Weather Advisory until 9 PM CST this evening for WIZ001- 002. MN...Wind Chill Advisory until noon CST Friday for MNZ010>012-018>021- 025-026-033>038. Winter Weather Advisory until 6 PM CST this evening for MNZ012- 020-021-037-038. LS...Small Craft Advisory until 4 AM CST Friday for LSZ121-142>148. Heavy Freezing Spray Warning until 10 PM CST this evening for LSZ146>148. Gale Warning until 6 PM CST this evening for LSZ140-141. && $$ UPDATE...Melde SHORT TERM...Melde LONG TERM...JTS AVIATION...JTS
Area Forecast Discussion
National Weather Service Detroit/Pontiac MI
951 PM EST Thu Jan 11 2018 .UPDATE... Well defined arctic boundary now seen exiting the eastern shores of lake Michigan on pace to rapidly sweep across southeast Michigan during the early morning period /04z-08z/. Extremely moist resident environment will continue to contribute to periodic bouts of rain overnight, both within the existing mild pre-frontal environment and accompanying the frontal passage. Pronounced downward spiral in temperatures with the fropa, as witnessed by the 19 degree drop in 2 hours at Chicago-Midway Airport. These trends continue to lend confidence in expectations for a high magnitude of low level cold air advection to eventually cool the near surface profile enough to leave a brief window for freezing rain, before the entire column drops below freezing and ptype moves to snow. Latest hi res guidance holding in support of this transition timeline. Primary area of uncertainty remains the behavior of the fgen response mid morning through early afternoon Friday, highlighted by the potential for a localized stronger axis of ascent to emerge should the forcing contract. No definitive signal yet per recent model evidence, which isn`t surprising given the scale, so no plans to provide any refinements to the going snow forecast with the evening update. && .PREV DISCUSSION... Issued at 725 PM EST Thu Jan 11 2018 AVIATION... A warm and increasingly moist deep layer southwest flow will maintain an extensive low stratus and periodic light to moderate showers and drizzle early tonight. An associated reduction in ceiling will favor predominate IFR conditions through the latter half of the evening, but with the higher terrain contributing to marginal LIFR conditions at PTK. The passage of an arctic front will then bring a transition in precipitation type from liquid to frozen Friday morning, as colder air surges in under developing northwest winds. The strength of the low level cold air advection will provide a 2-3 hour window mid morning where conditions become favorable for freezing rain, before the entire column cools sufficiently enough to support the transition to snow. A period of accumulating snowfall then expected from mid-late morning into the early afternoon. Current forecast will continue to highlight IFR level conditions in falling snow. However, the potential does exist for a localized heavier axis of snow to develop, which could result in a period of LIFR conditions. Confidence in placement of a heavier axis remains low at this time. Total snowfall accumulation of 2 to 4 inches, before snowfall tapers from northwest to southeast through the afternoon. For DTW...Short window for potential freezing rain remains centered 12z-15z Friday morning. Transition to accumulating snowfall thereafter through early afternoon. Current forecast calls for total accumulation of 2 to 4 inches. Firm southerly winds early tonight, turning northwesterly and increasing Friday morning. This may necessitate the eventual shift to northeast operation early Friday. //DTW THRESHOLD PROBABILITIES... * High for ceiling at or below 5000 ft through Friday. * Moderate for the occurrence of light freezing rain Friday morning /12z-15z/. * High in the transition from rain/freezing rain to snow late morning /after 14z-15z/. PREV DISCUSSION... Issued at 455 PM EST Thu Jan 11 2018 DISCUSSION... An extremely fluid forecast exists during the next 24 hours as an arctic boundary will impinge upon the area. The cold air will lead to the changeover of precipitation type from all rain to a period of freezing rain/sleet, eventually changing over to an all snow. Compounding matters is that shallow cold air advection will lead to rapidly falling temperatures across all of Southeastern Michigan Friday, resulting in high impact winter weather both with the expected snowfall amounts and the the flash freezing of earlier fallen precipitation. A Winter Weather Advisory is now in effect for all of Southeast Michigan between 09Z Friday-00Z Saturday. This will include both of the morning and evening commute times. It is likely that mixed precipitation and negative impacts would hold off until after the main morning rush hour push for a portion of metro Detroit. However, confidence is too low at this time to emphasize that message. Thus, the Winter Weather Advisory start time will begin at 09Z for all of the CWA. An extremely tight temperature gradient is forecasted along the arctic front as it pushes eastward over Lower Michigan at 06Z tonight. Impressive front, as 925mb temperatures of -22C will exist over portion of extreme eastern Lake Superior while temperatures of +12C exist near the city of Detroit. High end equivalent potential temperature/heat content for this time of year south of the front, as model data suggests PWATs exceeding 1.0 inch at 00Z this evening (greater than 300% of normal). Models are now advertising a slight slowing down of the mid to upper level frontal boundary as it arrives directly over the cwa on Friday. Big player from a dynamics perspective is a compact, but robust frontogenetic circulation that will ride northward along the frontal boundary in the 09-18Z time window. This fgen arises from an outstanding ageostrophic response from highly organized right entrance region dyanmics centered over the region. Additionally, pre-existing midlevel fgen residual to the upper Mississippi River Valley is expected to be drawn in and merge with the active response here locally. Two dimensional plan views show some merging of this larger scale forcing setting the stages for the event here locally. The overall narrative is one of the changing over of precipitation type from all rain to a period of freezing rain/sleet and all snow. Timing of the changeover will transition from the north to the south. Overall, looking at the period of mixed precipitation to be generally around 2 hours for any one location. All signs point to a period of high precipitation rates that brings ice accumulation of 10 inch in play. This includes favorable low static stability/convective instability above 10 kft agl, amount of available forcing and the freshening, frontal circulation. Total snowfall accumulations of 1 to 4 inches is expected on top of the earlier mix of freezing and rain and sleet. Some main thinking on this system. 1. One aspect of this forecast that remains highly uncertain is whether or not the fgen will collapse down in scale. There are some hi-resolution runs that are suggesting that convective precipitation, and very high rates will contract down to a single band on the order of tens of miles. The last forecast trends suggests possibly north of M59. If there were to occur than forecasted snowfall and/or icing amounts would need to be increased. Confidence in this is low at this time, hopefully, later hi-res runs including the HRRR will offer some useful guidance. 2. Forecast soundings resoundingly suggest that hydrometeors in the warm layer between 3.0 and 6.0 kft agl will be fully melted. This supports more in the way of freezing rain. It will be more difficult to refreeze a full liquid drop to get sleet. 3. Some model solutions suggest that the frontal boundary could slow down even more, and be slow to exit the forecast area. This could lead to some additional nuisance snow amounts in the far eastern cwa. However, bulk of moisture will have exited. 4. Main narrative is that conditions will not be pleasant with rapid onset of arctic cold and freezing of residual moisture. North winds of 20 to 30 mph is expected. Windchills are forecasted to fall into the -5 to -10 degree range Friday night. 5. There are a couple of reasons that Bay and Midland Counties were left out of the advisory at this time. The first is that overall system QPF is expected to be lacking, and the likely outcome is that they will miss the mixed precipitation types of this event. 6. Not completely clear yet how much of the Detroit Metro area will witness warm rain during the entirety of the morning rush hour. Arctic airmass in place Saturday (850 mb temps nearing -23C) along with long fetch northerly flow over Lake Huron will result in an increased likelihood of a band of lake effect snow to develop over the eastern Thumb. NAM model soundings still advertising good convergence/omega at 925mb and decent instability intersecting the saturated dendritic growth zone. Assuming this band stays persistent, a few inches of snow will be possible in and near Port Huron in the morning hours before flow backs to the northwest and pushes the band into the Canadian side of Lake Huron. Conditions for the rest of SE Michigan will stay quiet and gusty Saturday with highs staying in the mid to upper teens. Sunday will be a benign, cold day for all of SE Michigan. Morning lows will dip to the single digits as high pressure overhead will allow for some clearing and efficient radiational cooling to occur. Highs will recover to the upper teens as the high pressure moves off to the east and allows for some return southerly flow to filter back in. Next chance for snowfall will be Monday as a clipper is still progged to swoop through the Great Lakes. Model guidance is failing to reach consensus on the exact placement of the low, with the ECMWF showing it track over central Michigan and the GFS suggesting a track further south over central Ohio. Regardless, looking like an area-wide light snowfall of a couple inches will be possible as the system pivots through before exiting Tuesday morning. This clipper will also deliver a reinforcing shot of Arctic air that will keep temps some 10 degrees below average through midweek. Renewed northerly flow over Lake Huron will again lead to an increased chance for lake effect snow over the Thumb Tuesday and Wednesday. Otherwise, conditions will remain mostly quiet over the region through the rest of the week before the Arctic air moves off to the east and a warm up begins in time for next weekend. MARINE... Gusts to north northwest gales will develop across Lake Huron tonight as colder air spreads across the waters. Gale warnings remain in effect. In addition a heavy freezing spray warning has been issued to coincide with most of the gale warning area...including the nearshore zones. Maximum waves heights around 10 feet will be common along the exposed and ice free waters along the Thumb. Winds and waves will diminish as cold high pressure settles over the waters for the weekend. Winds will ramp up again early next week as a clipper moves through the Great Lakes region. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...Winter Weather Advisory from 4 AM to 7 PM EST Friday for MIZ049- 053>055-060>063-068>070-075-076-082-083. Lake Huron...Heavy Freezing Spray Warning from 10 AM Friday to 7 AM EST Saturday for LHZ362-363-441>443-462>464. Gale Warning from 3 AM Friday to 7 AM EST Saturday for LHZ441>443- 462>464. Gale Warning until 10 AM EST Friday for LHZ361. Gale Warning until 7 AM EST Saturday for LHZ362-363. Lake St Clair...NONE. Michigan waters of Lake Erie...NONE. && $$ UPDATE.......MR AVIATION.....MR DISCUSSION...CB/TF MARINE.......CB You can obtain your latest National Weather Service forecasts online at
Area Forecast Discussion
National Weather Service Austin/San Antonio TX
1001 PM CST Thu Jan 11 2018 .UPDATE... Additional counties have been removed from the Wind Advisory. Based on recent observations, we have cancelled the advisory for most areas along and west of Highway 281. No other changes to the forecast have been made at this time. && .PREV DISCUSSION... /ISSUED 827 PM CST Thu Jan 11 2018/ UPDATE... Winds have been steadily decreasing over the last few hours across south central Texas. Based on observational trends and hi-res guidance, we will cancel the wind advisory for areas generally along and west of Highway 83. Some of the hi-res models suggest gusty conditions will continue over portions of the Hill Country and along and east of the I-35 corridor this evening. We will continue to monitor, but may opt to cancel additional counties in a future update. Otherwise, updates have been made to the hourly temperatures, dew points and winds. PREV DISCUSSION... /ISSUED 553 PM CST Thu Jan 11 2018/ AVIATION... /00Z TAFS/ Nw winds will go from the brink of reaching AWW criteria at SAT to below 12 knots between 02 and 04Z. Will expect some subtle changes in wind direction at AUS before the winds become less gusty later in the evening. VFR skies should otherwise prevail, and the vsby restrictions from blowing dust look to have abated already. PREV DISCUSSION... /ISSUED 235 PM CST Thu Jan 11 2018/ SHORT TERM (Tonight through Friday Night)... Front has cleared the CWA. Windy conditions will continue through the evening, with highest gusts now through sunset. Will maintain the Wind Advisory through midnight, although most locations should fall below criteria before then. Temperatures have fallen into the upper 40s to mid 50s across the Hill Country this afternoon. Compressional heating that occurred along and south and east of the escarpment allowed temperatures to rise into the mid 70s, however temperatures should begin to fall in these locations through the late afternoon as cold air advection increases. Elevated light showers currently moving through the Hill Country should begin to decreasing coverage approaching the I-35 corridor per HRRR and 4KM Texas Tech WRF. A light freeze is forecast Friday morning across the Hill Country and Central Texas. Temperatures rebound into the mid 50s northeast to low 60s southwest for highs on Friday. A weak re-enforcing surge of high pressure late Friday night will send lows Saturday morning to freezing across most areas of the CWA, with the exception of possibly the Rio Grande. LONG TERM (Saturday through Thursday)... Cool conditions over the weekend as the aforementioned re-enforcing ridge settles over the region on Saturday and Saturday night. Highs Saturday are only forecast in the upper 40s to upper 50s. A hard freeze is expected Sunday morning. A return flow will setup Sunday night ahead of the next cold front. Slightly warmer Monday ahead of the front, but increasing clouds through the day. A large, deep trough will develop Monday through Wednesday from the Midwest into the Southeast U.S. and allow a glancing blow of arctic airmass to spill south into the area. The cold front is currently forecast to arrive Monday evening by both 12Z operational runs of the GFS and ECMWF. The ECMWF is a little more robust with developing light rain behind the front Monday night into Tuesday morning than the GFS. Will continue the 20-30 PoPs forecast during this time. Will have to watch temperatures closely for light freezing rain potential across northern areas of the CWA Tuesday morning if precip does linger longer and temps trend cooler, however am keeping this mention out of forecast for now. Much colder Tuesday, with highs not making it out of the low to mid 40s. Some of the raw guidance suggests highs could remain in the mid and upper 30s in across he northern CWA. The cold airmass will remain in place into Wednesday. Then the ridge shifts east and a warming trend and return flow is forecast Thursday. && .PRELIMINARY POINT TEMPS/POPS... Austin Camp Mabry 33 56 30 50 28 / 0 0 0 0 0 Austin Bergstrom Intl Airport 33 55 27 50 22 / 0 0 0 0 0 New Braunfels Muni Airport 33 58 29 52 24 / 0 0 0 0 0 Burnet Muni Airport 29 54 26 47 24 / 0 0 0 0 0 Del Rio Intl Airport 35 62 35 59 32 / 0 0 0 0 0 Georgetown Muni Airport 30 54 26 48 23 / 0 0 0 0 0 Hondo Muni Airport 33 62 29 57 25 / 0 0 0 0 0 San Marcos Muni Airport 33 57 28 51 25 / 0 0 0 0 0 La Grange - Fayette Regional 32 52 29 50 26 / 0 0 0 0 0 San Antonio Intl Airport 36 60 31 54 27 / 0 0 0 0 0 Stinson Muni Airport 36 60 32 55 27 / 0 0 0 0 0 && .EWX WATCHES/WARNINGS/ADVISORIES... Wind Advisory until midnight CST tonight for the following counties: Bastrop...Caldwell...Comal...De Witt...Fayette... Gonzales...Guadalupe...Hays...Karnes...Lavaca...Lee...Travis... Williamson...Wilson. && $$ Mesoscale/Aviation...Oaks Synoptic/Grids...24 Public Service/Data Collection...33
Area Forecast Discussion
National Weather Service Grand Rapids MI
1049 PM EST Thu Jan 11 2018 LATEST UPDATE... Update .SYNOPSIS... Issued at 330 PM EST Thu Jan 11 2018 A cold front will bring rain showers this evening that will become mixed with and then change over to light snow showers. Light snow and sleet accumulations of an inch or two are expected through midday Friday with relatively highest accumulations southeast of Grand Rapids. Temperatures will plummet into the 20s behind the cold front tonight. The cold air will stick around this weekend through next week with occasional snow showers. && .UPDATE... Issued at 1049 PM EST Thu Jan 11 2018 I continued the headlines as they are but I am very concerned that snowfall amounts will be more like 3 to 6 inches in the I-69 area by mid afternoon. This is supported by the latest runs of HRRR, HRRRX, RAP model, SPC SREF plums, NAM12 00z run just to name a few. The wave looks really good on the water vapor image loops and that wave is heading north northeast. We have a negative tilt upper wave over MS and AL this evening and those type systems tend to track north and west of where the models show them. This system should be coming into our area just as the deeper cold air arrives. Thus most of the precipitation should be snow. There will be strong winds with this system since the cold air is just starting to come in. Thus if we really get that FGEN band of heavier snow near I-69 the heavy falling snow and strong winds will make for dangerous driving conditions. The good news is the storm moves through quickly and in all areas the snow should be done by 4 pm or so. && .SHORT TERM...(This evening through Saturday night) Issued at 330 PM EST Thu Jan 11 2018 The cold front will bring rain showers into this evening that will change over to snow showers overnight as strong caa occurs after fropa. A very brief period of sleet is also possible. Based on a consensus of latest higher resolution short range guidance and qpf we expect snow accumulations of around an inch in our central fcst area. Snow accumulations of up to around two inches are expected over our se fcst area by midday Friday with locally higher amounts to near 3 inches possible near KJXN. Given plummeting temperatures after fropa and the precipitation and expectations for snow overnight into Friday morning we decided to hoist a winter wx advisory for the southern two thirds of our fcst area where travel conditions will likely become rather hazardous for the Friday morning commute. Decided against an advisory for our northern two rows of counties where very little snow (under an inch) is forecast and based on coord w/DTX and APX (thanks for extensive coordination on headline decisions DTX/IWX/APX). Cold and dry/tranquil wx is fcst for the vast majority of our fcst area Friday afternoon through Saturday night as high pressure gradually builds in from the northwest. A few flurries or light lake effect snow showers will just clip areas right along the Lake MI shoreline. .LONG TERM...(Sunday through Thursday) Issued at 330 PM EST Thu Jan 11 2018 Models are in relative agreement in tracking down a clipper low starting Sunday Night and lasting through Monday. Widespread accumulations look likely with some at least low impacts expected. I have increased POPs for this event given the better confidence. A reinforcing shot of arctic air moves in behind this departing system. Based on the low level flow...lake effect if any will be confined to the immediate lakeshore region. I do feature this highest POPs there with some potential for accumulations. Well below normal temperatures will continue. Mid level ridging arrives for the end of the week. The Gulf looks cut off through Friday. This pattern typically leads to moderating temperatures and less than normal precipitation. That could change next weekend as the Gulf is shown to open up as a Southern Rockies low kicks out into the Southern Plains. && .AVIATION...(For the 00Z TAFS through 00Z Friday evening) Issued at 628 PM EST Thu Jan 11 2018 IFR conditions continue to prevail at all of our TAF sites this evening. The cold front will be passing through by 03z or so and that will bring the winds to the west then northwest. Normally this would bring some clearing (behind a strong cold front) but this time there is a wave on the front. So even through the rain should end around 03z or so from the frontal system, then precipitation from the wave on the front will move in around 06z. Since by then the cold air will be in place I expect freezing rain, sleet and snow to start the precipitation again around 06z or so then it should change to all snow by 09z or so. I could see several hours of moderate snow at AZO, BTL, LAN AND JXN. For the western TAF sites skies will clear by 18z or so. The more eastern TAFS may stay in snow till late afternoon. && .MARINE... Issued at 330 PM EST Thu Jan 11 2018 The small craft advisory was extended through early Saturday morning. && .HYDROLOGY... Issued at 330 PM EST Thu Jan 11 2018 Snowmelt is expected into tonight, as warm moist air continues to invade the region. Most of the snow pack should melt, but not all of the melt water will make it into the river system before the cold air moves back in and locks it down later tonight through the weekend. There is still 1 to 2 inches of snow, mainly north of Grand Rapids. No excessive rainfall is expected with the warmup and amounts should be generally under one half inch through the warm period. This has resulted in minor river flooding scattered across Southwest Lower Michigan. Some ponding of water, away from the rivers, will be possible. The rivers will need to be closely monitored for ice breakup and potential ice jam flooding. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...Winter Weather Advisory from 3 AM to 6 PM EST Friday for MIZ059- 066-067-073-074. Winter Weather Advisory until 1 PM EST Friday for MIZ050>052- 056>058-064-065-071-072. LM...Gale Warning until 4 AM EST Saturday for LMZ844>849. && $$ UPDATE...WDM SYNOPSIS...Laurens SHORT TERM...Laurens LONG TERM...MJS AVIATION...WDM HYDROLOGY...63 MARINE...Laurens
Area Forecast Discussion
National Weather Service San Joaquin Valley - Hanford CA
408 PM PST Thu Jan 11 2018 .UPDATE...Updated air quality issues. && .SYNOPSIS... High pressure will build over the region for dry weather through at least next Monday. Late night and early morning dense fog is possible in the San Joaquin Valley through Monday. A cold front will move through the region next Tuesday bringing a slight chance of showers to the Sierra Nevada around Yosemite. && .DISCUSSION... Some patchy dense fog formed just before sunrise this morning then burned off by 10 AM. Large stratus deck over the San Joaquin Valley eroded from the east earlier with scattered to broken stratocumulus over mainly the southern SJ Valley now. The clearing led to warmer temperatures than expected with lower 60s across most of the Valley. A s/wv trough is passing over the Pacific Northwest as a ridge of high pressure sits just west of Baja CA. The ridge will build over the west through the weekend for dry and stable conditions. The big weather concern will be Tule Fog development the next several nights. The stage seems set for a good chance of more dense fog tonight but there is still some uncertainty regarding development time and coverage. The latest HRRR visibility forecast does paint a good portion of the Valley with dense fog forming after midnight, but other guidance is less bullish. We`ll be monitoring conditions this evening to determine the need for a Dense Fog Advisory. Safe to say there will be at least some patches of dense fog by early tomorrow morning. It is always a good idea during Tule Fog season to be prepared for hazardous travel conditions during the morning commute and allow for extra travel time. The pattern will remain favorable for fog through the weekend and probably Monday morning as well. There is good model agreement with the ridge giving way early next week as an upper trough moves over the Pacific NW and northern CA Monday night and Tuesday. There remains a slight chance for some light precipitation, mainly around Yosemite NP, but the trend is farther north with precip. Brief short wave ridging is progged to slide in next Wednesday, followed by a deeper trough Thursday and Friday. It is still a week away, but the models are indicating a return to wet weather for central California. && .AVIATION... MVFR visibility and ceilings and mist across the San Joaquin Valley through 18Z Friday. Patchy IFR conditions possible after 08Z Friday in Fog. VFR conditions will prevail elsewhere across the Central California Interior during the next 24 hours. && .AIR QUALITY ISSUES... On Friday January 12 2018... Fireplace/Wood Stove Burning Status is: No Burning Unless Registered in Kern... Kings and Tulare Counties. Further information is available at && .CERTAINTY... The level of certainty for days 1 and 2 is medium. The level of certainty for days 3 through 7 is medium. Certainty levels include low...medium...and high. Please visit for additional information an/or to provide feedback. && .HNX Watches/Warnings/Advisories... NONE. && $$ public...DCH avn/fw...Molina synopsis...DCH
Area Forecast Discussion
National Weather Service Northern Indiana
849 PM EST Thu Jan 11 2018 .SYNOPSIS... Issued at 313 PM EST Thu Jan 11 2018 A winter storm will bring a mix of precipitation to the forecast area tonight into Friday, with freezing rain, sleet both possible. Mixed precipitation will change over to all snow from northwest to southeast as a cold front moves through tonight, with snow gradually tapering off by Friday afternoon and evening. Expect 1 to 3 inches of snow and minor ice accumulations. Both the Friday morning and evening commutes will be impacted. See the latest winter weather statement for details. && .UPDATE... Issued at 840 PM EST Thu Jan 11 2018 Sfc cold front is quickly advancing into northwest portions of the area this evening with a thin line of enhanced showers developing along the stronger low level convergence from South Bend to Lafayette. Temperatures to sharply drop with approach of this front. Precipitation type/amounts obviously remain the primary forecast issue for tonight. Arctic air mass will continue to undercut warmer low level air this evening resulting in transition to freezing rain late this evening and early overnight. The approach of disjointed the upper level trough tonight should tend to strengthen low level fgen fields over the next several hours, with post-frontal 900-700 mb forcing becoming more prevalent in the 04Z-10Z timeframe. Tightening low level thermal gradient in response to strengthening low level fgen will be a challenge to resolve in terms of warm layer magnitude and accompanying precip types, with some slowing of tight thermal gradient for the overnight hours across central/eastern portions of the forecast area. There still appears to be a 2 to 4 hour window of freezing rain potential before warm layer is eroded to more of a sleet profile, with eventual changeover to snow. Near term forecast profiles suggests arctic intrusion across western half of area may marginally support some refreezing of melted hydrometers aloft, that would be even more supportive of sleet over freezing rain. Latest HRRR trends even a bit more bullish in maintaining weak warm layer across the west through most of the warm overnight hours that may prolong sleet a bit more than previously indicated. Uptick in precip/coverage intensity noted over past several hours across western Kentucky/southern Illinois, although LLJ orientation would tend to favor best narrow theta-e advective forcing lifting north-northeast across eastern portions of the forecast area during the early overnight. However, expecting additional post sfc-frontal development overnight given the above factors. Previous forecast seems to have overall situation in hand, and only tweaks that will be made at this time may be to slightly prolong sleet mention across western half of the area overnight before changeover to snow. Will maintain general distribution of snow/ice accumulations, although may be seeing increasing tendencies of a good deal of sleet overnight/early Friday morning for many locations. Far east/southeast will be slow to changeover to wintry mix overnight, with extreme southeast more in the after daybreak period. && .SHORT TERM...(This Evening through Friday) Issued at 313 PM EST Thu Jan 11 2018 ...Wintry Mix of freezing Rain, Sleet, and Snow Expected... Headline Decision: Winter Weather Advisory for all counties in the CWA. See the latest winter weather statement for details on timing, etc. Well we`ve finally reached decision time. Thankfully, models are still in agreement with regards to keeping the axis of heaviest precipitation to our east. That being said, we still have a winter weather situation on our hands with the wintry mix expected tonight, and the transition to snow by late Friday morning. Snow will continue through early afternoon in the west, and by the evening in the east. Lake effect snow will develop with north- northeasterly winds in the wake of the system Friday afternoon into the remainder of the period. The real tricky aspect: We`ll only have a short window of freezing rain/sleet, up to about 2-3 hours for most locations. How much of this will be freezing rain before it turns to sleet/snow, and how much ice? From latest model runs, thinking it will be brief enough that we won`t have more than 0.10" of ice accumulation...and this is probably a higher-end scenario because we will could see a greater mix of sleet than what we have in the forecast. Adding to concerns, the 12Z NAM develops a bullseye of QPF over our east-central CWA in response to the enhanced forcing in the right entrance region of a strengthening 300MB Jet between 9-15Z, which stretches over northern Lower Michigan/Ontario/Quebec. The enhanced upper level divergence works to tilt our trough negatively and contract (strengthen) the frontal zone across our area. Looking at a cross section through the frontal zone, we see a brief period of decent instability/CSI. If it occurs, this will favor the development of heavier bands of snow, which supports the idea of the NAM`s increase in QPF (including the FWA area). Overall, however the time the ingredients come together is pretty short-lived, and don`t expect too much in the way of additional ice accumulations beyond those forecasted at this point. Furthermore, thinking it will largely be more snow/sleet than any freezing rain at the times of greatest instability. In the end, put 2-3" snow in the forecast for the eastern half of the advisory given the potential. Adding to concerns, observations of the impending cold front rapidly progressing across IL shows a large temperature gradient and sharp wind shift to the northwest. Temperatures across eastern IL are in the upper 50s to around 60F, but behind the front they quickly drop to around 15-20F...which brings the concern for a flash-freeze scenario. With recent snowmelt/ongoing rain, this brings the slick road concern to the forefront (regardless of how much freezing rain falls). Overall, expect only 1-3" of snow accumulation as forecast soundings suggest riming and low snow ratios will probably cut down snow totals. Icing will be less than 0.1" total. If you must travel tonight or Friday...DRIVE SLOW ON ICE AND SNOW. && .LONG TERM...(Friday Night through Thursday) Issued at 412 PM EST Thu Jan 11 2018 ...Winter is Back: Cold Air and Lake Effect... Cold air filters in behind the strong low pressure system to our east, bringing highs into the teens and 20s, and lows into the single digits and teens through next week. As far as the pattern aloft, we`ll see our broad upper level trough shift overhead, with several embedded shortwaves pinwheeling through the flow into Sunday. At the surface, strong arctic high pressure to our northwest (1044 mb high) will impinge southeastward into our area as low pressure that caused our recent winter weather shifts out of the area. This will give us a pretty decent north-northeast wind that will continue into Saturday before shifting northwest and weakening Saturday evening. With our arctic airmass sliding across the lake, we`ll see some lake effect potential, with models appropriately suggesting the development of a single band down the axis of Lake Michigan through Saturday. While instability is favorable, with delta theta e values between -3 and -5, the moisture is lacking. Dewpoint depressions of 10-15C move in pretty rapidly,and inversion heights sit at around 3000-5000 feet. Right now, have around 1" or so of accumulation from late Friday afternoon into Saturday, with other areas near the lakeshore even less than that. We`ll see how things develop after the system exits our area tomorrow to add more detail in. Things will wind down as winds back around to the west southwest Sunday morning, we`ll see things fall apart as they move onshore into our Michigan Counties, with some of the Michigan areas seeing light accumulations. Otherwise, Monday into Tuesday we`ll see an upper level low plummet into the Great Lakes Region, with our CWA in the left-exit region of a decent upper level Jet. We see decent 850-500mb qvector convergence enter into our western CWA by Monday morning, shifting eastward through the afternoon. Given the cold temps, this will be snow. ECMWF/GFS still place the surface low center in slightly different locations, but it is something to keep an eye for this period. A northerly fetch will develop over Lake Michigan Wednesday into Wednesday night as Monday/Tuesday`s surface low pressure system exits the area and high pressure inches in from the northwest. This will bring yet another single band set up to Lake Michigan, which will impact the northwest portions of our forecast area until flow becomes more west-northwesterly Thursday into Friday. Snow showers will gradually taper off as an upper level ridge builds in. && .AVIATION...(For the 00Z TAFS through 00Z Friday Evening) Issued at 702 PM EST Thu Jan 11 2018 Sfc cold front is approaching the IL/IN stateline at this hour and should reach the KSBN vicinity around 03Z, and KFWA in the 05Z-06Z period. Temperature gradient with this front is very strong and current temperatures in the mid to upper 50s will rapidly cool into the upper 30s by late evening, and then into the mid and upper 20s overnight. This strong arctic air mass undercutting warmer air will lead to about a 2 to 3 hour window of freezing rain potential, followed by period of sleet before changing to snow late tonight from west to east. Timing of previous TAFs with this precip type evolution still appears to be very reasonable when considering current trends and no significant changes were made for the 00Z TAFS. While the duration of the freezing rain is expected to be small, some impressive precip rates could occur during this short window. Accumulating snow expected at terminals late tonight into Friday morning before tapering at KFWA for the afternoon hours. Gusty south-southwest pre-frontal winds will remain gusty behind the front from northwest in strong cold advection through this period. IFR cigs in vicinity of frontal boundary and just behind the frontal boundary are expected, before transitioning to MVFR cigs deeper into the cold air late tonight/Friday. However, periods of IFR/LIFR conditions may hold through much of Friday morning due to vsby restrictions in changeover to snow. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...Winter Weather Advisory from 3 AM to 7 PM EST Friday for INZ007- 009-018-025>027-032>034. Winter Weather Advisory until 1 PM EST /noon CST/ Friday for INZ003>006-008-012>017-020-022>024. MI...Winter Weather Advisory from 3 AM to 7 PM EST Friday for MIZ080- 081. Winter Weather Advisory until 1 PM EST Friday for MIZ077>079. OH...Winter Weather Advisory from 3 AM to 7 PM EST Friday for OHZ001- 002-004-005-015-016-024-025. LM...Small Craft Advisory until 4 AM EST Saturday for LMZ043-046. && $$ UPDATE...Marsili SYNOPSIS...MCD SHORT TERM...MCD LONG TERM...MCD AVIATION...Marsili Visit us at Follow us on Facebook...Twitter...and YouTube at:
Area Forecast Discussion
National Weather Service Louisville KY
1018 PM EST Thu Jan 11 2018 .Forecast Update... Issued at 1018 PM EST Thu Jan 11 2018 Another complex Ohio Valley winter storm, with a variety of model solutions from which to choose. A cold front extends from Michigan to the Wabash Valley to the lower Mississippi Valley. This front is pushing eastward quickly. However, the 18Z and 22Z RAP runs verified well with its 01Z placement, as did the WRF-ARW. These models showed the band of heaviest snow, and the best ice potential, within the warning that is already in effect. They did suggest a slight eastward trend, however, with the snow. SREF plumes show a wide variance in snowfall totals, with an average of about three inches at Louisville, roughly in line with the current forecast. The most recent NAM is showing a couple bands of heavy snow, including one over the Blue Grass. However, the NAM has shown little run-to-run consistency over its last 4 runs, leading to somewhat less confidence in its solution. It actually had better consistency 5 to 7 runs ago, at which time it painted the snow farther west. The CMC has told a similar story, with inconsistencies over its past couple runs but better agreement in earlier runs, placing the band farther west. So, going with the short term models that have verified well lately and are showing a similar trend, have bumped up snowfall amounts in the Blue Grass and have pushed the warning one more tier of counties eastward. This was coordinated with ILN and JKL. Kept the ice amounts and placement the same for now. Another thing to consider here is the wind. Northwest and north winds will be in the 10 to 20 mph range, with gusts to 30 mph Friday afternoon and evening. Ice covered branches will be vulnerable to such winds, and blowing snow may become a problem in the evening. Wind chills will fall into the teens by evening. Nothing is set in stone with this forecast, and it is likely that further alterations will be made by the overnight shift as new data come in. && .Short Term...(Tonight through Friday night) Issued at 255 PM EST Thu Jan 11 2018 ...Wintry Precipitation Will Impact Travel Friday and Friday Night... Deep southerly flow continues to feed unseasonably warm and humid air into the Ohio Valley. Weak isentropic lift touched off scattered showers earlier, but we are now mainly dry. Temps generally in the 60s this afternoon, and will initially be slow to fall this evening. Winter storm is still poised to have substantial impacts Friday into Friday night. Main challenges are timing of the transitions to freezing rain and eventually to snow, and amounts of ice and snow accumulation. Still expect the transition to freezing rain during the morning along and west of Interstate 65 as the cold low-level air undercuts the warm SW flow aloft. The duration of the freezing rain in this area is longer than previously advertised, and opens a wide window to pick up a quarter inch of ice accumulation. As the Arctic air heads farther east, low pressure over the Tennessee Valley will hang up the cold front, allowing the cold air aloft to catch up, and narrowing the window for freezing rain as the transition happens in the Bluegrass late in the afternoon. Should be mostly snow by late afternoon as the upper low swings across Kentucky, with a potential deformation band setting up somewhere over north central Kentucky or southern Indiana. Snow totals of 2-4 inches are expected along and north of the Western Kentucky and Bluegrass Parkways, with the majority of that area trending toward the low end but locally exceeding 4 inches where the heavier band sets up. Winter Storm Warning has been posted west of I-65, and one tier of counties farther east. To the east of the warning area, a Winter Weather Advisory has been posted. Gave some thought to expanding the warning into the Bluegrass, as there is an outside shot of the deformation band setting up that far east, especially if the weaker and faster ECMWF is right. However, this is also where uncertainty remains the highest, as loss of ice aloft will cut into snow amounts as well as QPF, especially southward toward Lake Cumberland. While there are still question marks about precip types and amounts, impacts to travel are likely along and west of I-65 during the morning commute, and a virtual certainty throughout the area by Friday afternoon. && .Long Term...(Saturday through Thursday) Issued at 305 PM EST Thu Jan 11 2018 Arctic high pressure builds in on Saturday, plunging the Ohio Valley back into the deep freeze. Clipper system swings through on Monday, and could bring minor snow accumulations. Very cold temps through the period, with highs below freezing. Coldest temps Mon night and Tue night, when snow cover may allow temps to radiate down close to zero. Sub-zero wind chills likely those two mornings. && .Aviation...(00Z TAF Issuance) Issued at 649 PM EST Thu Jan 11 2018 A line of scattered showers has pushed east of HNB this evening, so dry conditions prevail for the moment at all TAF sites. HNB has dropped to the Fuel Alternate MVFR range, and ceilings will gradually lower to MVFR tonight and IFR during the Friday morning hours. Timing on the IFR is around 02z for HNB, 08-09z for SDF/BWG, and 13z for LEX. IFR is then likely through much of Friday with widespread showers. As colder air pours into the region Friday morning and afternoon, a changeover to wintry precip is expected. FZRA is possible at HNB as early as 10z and 14z at SDF. As the atmosphere continues to cool, sleet will mix in with freezing rain. Sleet should become more common from west to east between 14-20z. Finally, a changeover to all snow is likely from west to east between 16-22z. By midday, icing could start to cause issues on pavement as well as elevated surfaces and power lines. The worst impacts are expected during the afternoon and evening hours, when the bulk of the wintry weather will occur. Storm total ice accumulations of 0.10-0.25 inches are expected, followed by 2-4 inches of snowfall. A couple of the northern TAF sites could be impacted by a localized heavier band of snow that results in more than 4 inches. Forecaster Confidence: Ceilings : High Visibilities: Moderate Winds : High Precip Type : Moderate && .LMK WATCHES/WARNINGS/ADVISORIES... IN...Winter Storm Warning from 4 AM EST /3 AM CST/ Friday to 1 AM EST /midnight CST/ Saturday for INZ076>079-083-084-089>092. KY...Winter Storm Warning from 4 AM EST /3 AM CST/ Friday to 1 AM EST /midnight CST/ Saturday for KYZ023>035-038-039-045-046-053- 054-061>063-070>074. Winter Weather Advisory from 10 AM EST /9 AM CST/ Friday to 7 AM EST /6 AM CST/ Saturday for KYZ036-037-040>043-047>049- 055>057-064>067-075>078-081-082. && $$ Update...13 Short Term...RAS Long Term...RAS Aviation...EBW
Area Forecast Discussion
National Weather Service Chicago/Romeoville, IL
821 PM CST Thu Jan 11 2018 .UPDATE... 821 PM CST In coordination with DVN, ILX, and MKX have opted to cancel the winter wx advisory early. No additional measurable precipitation is expected tonight roughly north and west of I-55. There had been concern about a flash freeze and "black ice" forming this evening, however have not had any reports of this yet and after spending nearly 2 hours below freezing here at the WFO, pavement is mostly dry with just a few moist patches that have yet to freeze. The recent warm spell where dewpoints rose into the mid-upper 50s likely sent pavement temps well into the 40s and lower 50s and current pavement temperatures in Chicago and northwest IN remain in the 40s, even in the upper 40s on the warmest sensors in Chicago. By the time the pavement temps cool to freezing, it is likely they will have had ample time to mostly dry out. Could still eventually be some icy spots develop tonight, mainly on bridges and overpasses, but with no measurable precip expected, felt comfortable canceling the advisory early. Farther southeast, mainly to the east of I-57, a secondary surge of precip is expected to light north into the area late this evening and especially overnight. Forecast soundings suggest that the bulk of this precipitation could fall as sleet with some freezing rain or snow possible. Did add Livingston County to this advisory grouping and kept them going until 1 am as the HRRR still shows SE Livingston being clipped by some precip late this evening. Snow/sleet combination could accumulate up to a quarter to a half inch over NW IN and adjacent areas of EC IL, with a glaze of up to a tenth of an inch possible. As alluded to earlier, pavement temps remain well above freezing, which could limit the impacts to travel from this precip, especially the freezing rain, but eventually temps should cool enough for freezing/frozen precip to stick on roadways especially late tonight. Overall, going forecast is in good shape and no big changes needed this evening. - Izzi && .SHORT TERM... 111 PM CST Through Friday... Messaging for today`s weather continues to center on a window of mixed precipitation this afternoon across north central Illinois, getting close to the Chicago metro area, a dramatic drop in temperatures creating hazardous road conditions due to wet roads, then a resurgence of mixed precipitation in the form of snow and sleet across northwest Indiana. Very mild conditions are currently in place with several bands of rain occurring. A well defined upper level low/shortwave is tracking through Iowa and this wave is driving a more significant band of precipitation. It is this second wave that will present concerns for areas across north central Illinois this afternoon as a strong cold front comes crashing in. Upstream observations depict a rapid transition to wintry precipitation, with some sites headed to freezing rain, others quickly heading to sleet snow. Expect a similar situation in parts of our area as such strong low level cooling would likely transition from a window of freezing precip to sleet. Areas northwest of the Chicago area will have the cold air arrive in time this afternoon to present the highest concern for mixed precipitation. The concern begins after about 3 pm across north central Illinois through about early evening, which would present concern during busy travel times. Once the cold air arrives in the Chicago metro this evening, there may not be much precipitation left. But with damp/wet conditions today and upstream locations already reporting significant travel problems just from the rapid freeze of the wet surfaces, this may end up being the more significant concern for the Chicago area. The period of highest concern for metro area is after 6-7pm for several hours. Strong pressure rises behind the front will lead to blustery northwest winds which will get to 30-35 mph. Wind chill readings this evening will correspondingly plummet to the single digits through the evening, and it is likely temperature trends are too slow with the speed of the drop. Areas southeast of I-57 stand the best chance for what will largely be sleet to snow overnight where accumulations still look on track. QPF numbers are a tad higher over northwest Indiana, peaking overnight as the next wave of moisture still well south of the area but embedded in the southwest flow ahead of the upper trough shifts into Indiana, where sleet and snow accumulations do still appear likely. Some of this precip may sneak back into northeast Illinois but it would be light. Temperatures continue to fall and will end the night with lows in the lower teens toward RFD to near 20 across northwest Indiana, and wind chills in the single digits to around zero. Cold north winds will transition the area to lake effect concerns, which we will address in the long term discussion. KMD && .LONG TERM... 234 PM CST Friday night through Thursday... Main forecast concerns include lake effect snow Friday evening through Saturday afternoon... next round of light snow with clipper type system Sunday evening through Monday... and return to below average temps through much of the period. Expect period of light to perhaps locally moderate lake effect snow to develop Friday afternoon and continue into Saturday afternoon before shifting off to the east of the forecast area by evening. Expect a transitory and evolutionary nature of the lake effect snow... beginning as a wind parallel banded event... with then perhaps a more dominant band setting up in the north flow overnight Friday into Saturday morning for several hours... before evolving back to a more multiple banded event. Model guidance continues to oscillate a bit on the boundary layer wind orientation with this event... which is of course critical to where the snow will set up. Latest runs of the NAM/3 km NAM nest trending slightly more northerly in low level wind direction (rather then NNE) which would impact more just the eastern portions of Cook and Will Counties along with Indiana. Expect this at the onset of the event... when the lake surface to 850 mb temp difference exceeds 15-17 deg C... which increases to 20 by Friday evening. Limiting factor in lake snow band development however will be low inversion heights... around 4500 ft through Friday evening. Most impressive snow of the episode appears possible overnight Friday into Saturday morning as thermal instability peaks and inversion heights rise slightly. During this time model low level wind fields suggesting some along shore/coastal convergence setting up which may enable a more dominant band. By this evolution of the event it would be Lake and Porter Counties in Indiana where concern would be greatest. May see accumulations of a few inches from this band with a moderate snowfall rate at times. Inversion height is lowering again somewhat by Saturday afternoon with boundary layer winds turning more west of north. With this expect nature of the lake effect snow to transition back to more of a wind parallel banded (and hence lighter snowfall) with the snow at this time all in northwest Indiana and on an eastward moving path. All the above being said... conditions and guidance will be monitored closely the next 24-36 hours since very subtle changes in the low level winds will play a key role in where snow falls and hence who gets it. Will maintain high pops and snow accumulations of 1-3 inches with this event through Saturday evening... with some isolated 4-5 inch amounts possible under where any more dominant band sets up... in Lake and Porter Counties in Indiana. This forecast will continue to be refined however as the event draws nearer. Expect lake effect snow to shift east of Porter County by Saturday evening. A brisk north wind will contribute to blowing and drifting snow throughout this episode and help cause sharply reduced visibilities at times. Hence significant travel impacts can be expected. Progressive upper pattern early next week as large trough/upper low rotates into the western Great Lakes Monday. Low then cuts off Tuesday however in response to amplifying pattern with strong height rises over the Atlantic seaboard. This maintains broad cyclonic flow across the region through mid week. Fast moving clipper like system moves quickly southeast into the area Sunday evening via evolving northwest flow aloft. Expect broad area of light snow along/ahead of the wave with strong divergence aloft given favorable upper jet positioning helping produce broad ascent. Will maintain high pops with accumulating snow a good bet at this point. As surface low stalls over lower Michigan by Monday evening in response to evolving cut off low and system becoming vertically stacked... the local area comes under an extended period of broad cyclonic flow. The potential for a lake enhanced snow episode then comes into the picture... especially Tuesday given continued favorable thermal instability (lake surface to 850 mb temp difference remaining 18-20 deg C) and a disappearing capping inversion. Considerable differences in the low level wind fields between the models however raises considerable uncertainty as to what degree this may take place and if it does, exactly where. Hence will need to continue to closely monitor this period. In any event a return to below average temperatures is certain for next week with highs mainly in the teens early in the week... moderating to the 20s by Thursday. Ed F && .AVIATION... For the 00Z TAFs... 608 pm...Forecast concerns include freezing drizzle this evening... light snow/flurries early Friday morning and then lake effect snow showers Friday afternoon into Friday evening. The back edge of light rain will move northeast of ord/mdw in the next hour or so with the chance of a little sleet as colder air continues to spread into the area. It appears this light rain will end prior to air temperatures falling below freezing. However... further southeast at gyy...light rain or rain showers may continue through the mid/late evening with air temperatures below freezing with freezing rain possible there. Elsewhere...chances for prevailing precip look low and have maintained tempo freezing drizzle but confidence for precipitation west of gyy is low. Short term guidance is showing a band of light snow or flurries developing over northeast IL prior to sunrise and while confidence for exactly how strong this precip may be is low...added flurries for a few hours toward sunrise to account for this potential. Lake effect snow is expected to develop Friday morning and continue into Friday night but there remains uncertainty regarding how far west and potentially into northeast IL...this lake effect snow may move. For now have kept ord dry with prob mention at mdw and tempo mention at gyy. Gusty west/northwest winds will slowly turn more north/northwest tonight and then northerly Friday morning with gusts increasing toward 30kts Friday morning. Wind directions may favor a more north/northeast direction later Friday morning into Friday afternoon but confidence for specific wind directions is low. Winds are expected to slowly turn back north/northwest Friday evening. cms && .MARINE... 308 PM CST A very strong cold front will move west to east across Lake Michigan late this afternoon/early evening... with a rapid wind shift and increase in wind speeds to gale force by early to mid evening. Northwest gales become North overnight and continue Friday and Friday night as strong low pressure moves east into the Appalachians and strong high pressure builds into the upper Midwest by Saturday morning. The ridge of high pressure will move across the lake Sunday... as a clipper type low pressure area then moves quickly across the southern Great Lakes Monday and slows over the eastern Great Lakes Tuesday. Ed F && .LOT WATCHES/WARNINGS/ADVISORIES... IL...Winter Weather Advisory...ILZ023-ILZ033-ILZ039 until 6 AM Friday. Winter Weather Advisory...ILZ032 until 1 AM Friday. IN...Winter Weather Advisory...INZ001-INZ002-INZ010-INZ011-INZ019 until 6 AM Friday. LM...Gale Warning...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-LMZ745...3 AM Friday to 6 AM Saturday. Small Craft Advisory...nearshore waters until 3 AM Friday. Small Craft Advisory...LMZ740-LMZ741-LMZ742...6 AM Saturday to 3 PM Saturday. Small Craft Advisory...LMZ743-LMZ744-LMZ745...6 AM Saturday to 6 AM Sunday. Gale Warning...LMZ777-LMZ779 until 3 AM Saturday. && $$ 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
National Weather Service Shreveport LA
928 PM CST Thu Jan 11 2018 .UPDATE... Very strong cold air advection in the wake of the cold front now which extends from near ELD to just west of IER as of 03z. Most of the more moderate rainfall is out ahead of the frontal boundary across portions of South Central Arkansas into North Central and Northeast Louisiana but post frontal light rain continued to be observed across portions of Northwest Louisiana into Southwest Arkansas. Calling around to our west and northwest, it does not appear that echoes near and to the west of TYR are making it to the ground as ceilings ranging from near 8-12kft along the back edge of the cloud cover to the west of TYR with the ceiling at TYR coming up rapidly. Newest 00z runs including the latest run of the HRRR continue to be in good agreement with the center of the trough extending from near NE OK into NW LA and SE TX by 06z this evening and near the Tenn and Lower Miss River Valley by 12z Fri morning. Area of mid level lift in association with the left front quadrant of 90kt upper jet along the back side of the trough of low pressure should continue to produce enough forcing for some precipitation to continue through the remainder of the night but mainly across Northern Louisiana into Southern Arkansas. Hourly trends were not keeping up with the rapid post frontal CAA in place so had to lower temperatures a few degrees for the overnight period which resulted in needing to make some necessary changes to precip type. Transitioned from rain to light freezing rain/sleet and/or light snow a little quicker as well in addition to needing to add the mention of light freezing rain to our extreme eastern parishes but this would be closer to sunrise or shortly thereafter if the temperature can get to freezing before the precipitation exits the region. Contemplated hoisting a Winter Weather Advisory but the window of opportunity is very brief if at all before the precip exits our region to the east. Did make the change from no accumulation to little if any accumulation expected for the above mentioned areas and we will continue to monitor the transition when it happens. If intensities pick up under this strong CAA pattern, then a quick Winter Weather Advisory may be necessary during the overnight hours. Updated forecast package already sent...13. && .PREV DISCUSSION... /issued 521 PM CST Thu Jan 11 2018/ AVIATION... TSRA conditions expected across MLU/ELD in conjunction with a cold front that is moving east across the region. Northwest winds to increase to 25 to 30 knots with higher gusts across TYR/GGG/TXK/SHV terminal sites with slightly lower wind speeds elsewhere. Otherwise, -SN conditions possible from 12/08Z-12/12Z across SHV/ELD/MLU/TXK terminal sites. Otherwise, winds to gradually decrease on Friday. /05/ && .PRELIMINARY POINT TEMPS/POPS... SHV 28 44 27 42 / 50 0 0 0 MLU 33 42 25 40 / 70 20 0 0 DEQ 24 42 22 40 / 20 0 0 0 TXK 26 42 24 39 / 30 0 0 0 ELD 30 42 23 39 / 60 10 0 0 TYR 26 44 26 42 / 20 0 0 0 GGG 27 45 25 42 / 20 0 0 0 LFK 29 47 27 46 / 20 0 0 0 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...Lake Wind Advisory until noon CST Friday for ARZ050-051-059>061- 070>073. LA...Lake Wind Advisory until noon CST Friday for LAZ001>006-010>014- 017>022. OK...Lake Wind Advisory until noon CST Friday for OKZ077. TX...Lake Wind Advisory until noon CST Friday for TXZ096-097-108>112- 124>126-136>138-149>153-165>167. && $$ 05/13
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