Aikyam-Lab/Synoptic-Bench huggingface dataset:
THIS HIGH SHOULD BE CLOSE ENOUGH TO THE UPPER MISSISSIPPI RIVER VALLEY THAT OUR SURFACE GRADIENT WILL ONLY SUPPORT 5 KNOTS OR LESS OF WINDS. THE LOW TEMPERATURES WOULD BE A BIT WARMER THAN FORECAST AND WE WOULD SEE SLIGHTLY WARMER WIND CHILLS.
HAVE CONTINUED WITH SLIGHTLY HIGHER POPS IN THE HIGH TERRAIN AND FOOTHILLS. A SHORT WAVE RIDGE IN THE NORTHWEST FLOW WILL BRING CLEAR SKIES TO THE REGION TONIGHT ALLOWING THE MERCURY TO PLUMMET BELOW ZERO FOR MANY LOCATIONS. WITH ADDITIONAL ENERGY DROPPING FROM THE PACIFIC NW INTO THE GREAT BASIN AND PULLING A WEAK TROUGH AXIS INTO THE ROCKIES.
COLD HIGH PRESSURE SINKING SOUTHWARD THROUGH THE PLAINS WILL INCREASE THE DEPTH OF THE DENDRITIC GROWTH ZONE AND EXTEND IT INTO THE BOUNDARY LAYER ACROSS FAR SOUTHWEST KANSAS DURING THIS SHORT TERM PERIOD. COLD OVERNIGHT TEMPERATURES WILL RETURN TO THE SINGLE DIGITS ACROSS A BROAD AREA BY EARLY FRIDAY MORNING, AFTER PROBABLY NOT EXCEEDING THE LOW 20S ANYWHERE IN THE FORECAST AREA ON THURSDAY.
335 PM EST THU FEB 26 2015 LOW PRESSURE OFF THE MID-ATLANTIC COAST WILL CONTINUE MOVING OUT TO SEA OVERNIGHT. CANADIAN HIGH PRESSURE WILL BUILD INTO THE AREA FOR THE WEEKEND. LOW PRESSURE OFF THE MID-ATLANTIC COAST WILL CONTINUE MOVING NORTHEAST AND OUT TO SEA. CANADIAN HIGH PRESSURE CENTERED OVER THE NORTHERN PLAINS WILL SLIP SOUTHEAST INTO THE CENTRAL MS RIVER VALLEY OVERNIGHT.
A 850-700 MB TROUGH WILL BE CROSSING THE AREA TONIGHT. THE MAIN IMPACT WITH THIS TROUGH WILL BE TO STRENGTHEN COLD ADVECTION ALOFT.
IN THE HIGH COUNTRY. RIDGETOP WINDS WILL BE MORE WESTERLY OVERNIGHT.
CURRENTLY FRONT IS LOCATED OVER NORTH CENTRAL TEXAS HEADING SOUTH WITH HIGH PRESSURE GRADUALLY BUILDING ACROSS THE COASTAL WATERS. MOST LOCATIONS WEST OF HWY 77 AND 281 WILL EXPERIENCE TEMPERATURES IN THE LOW 40S WHILE EAST OF HWY 77 TEMPERATURES WILL BE NEAR 50.
346 PM CST Thu Feb 26 2015 An upper level trough off the Vancouver, Canada coastline will dig southeast across WA and OR during the next 24 hours. A minor upper level trough across the four corners area will dig southeast across northern TX and OK, bringing a chance for measurable snow along across OK and north TX on Friday. The increased cloud cover and western edge of low-level cold air-mass will keep highs in the low to mid 20s.
BUT GENERALLY LIGHT AND OF A SPOTTY NATURE GIVEN LACK OF A STRONG COLD FRONT. FORMING AN ELONGATED NORTHEAST TO SOUTHWEST-ORIENTED TROUGH AXIS AS THE STORM STARTS TO SPLIT.
WILL BE UPDATING THE COASTAL FORECAST FOR INCREASING WINDS THIS EVENING IN RESPONSE TO THE REINFORCING COLD FRONT. REINFORCING COLD FRONT AROUND THE ARKLATEX WILL MOVE THROUGH ALL BUT LOW4ER ACADIANA BY AROUND NOON AND SHOULD FILTER THROUGH THE REMAINDER OF THE AREA AND THE COASTAL WATERS BY SUNSET. THE NEXT WEATHER MAKER IS A FAST MOVING DRY COLD FRONT THAT HAS MOVED THROUGH THE DALLAS/FORT WORTH AREA THIS MORNING AND WILL MAKE SHREVEPORT AFTER SUNRISE. COLD AIR ADVECTION BEHIND THE FRONT ALONG WITH CLOUDS THIS MORNING WILL HELP TO HOLD TEMPERATURES IN THE LOW TO MID 50S TODAY.
THIS WINDOW IS RATHER SMALL FOR ALL BUT THE RIDGES BEFORE SUBSIDENCE TAKES PLACE. ONLY ADDING ABOUT AN INCH TO THE HIGHEST ELEVATIONS OF PA/WV/MD. WITH HIGH PRESSURE OVERHEAD FRI NIGHT/SAT MORNING THE BOTTOM WILL ONCE AGAIN FALL OUT ON THE TEMPERATURES AS IDEAL RADIATIONAL COOLING WILL SET UP. DESPITE WARM AIR ADVECTION TAKING PLACE IN THE LOW- TO MID-LEVELS. THE ATMOSPHERE SHOULD DECOUPLE AND WONT ALLOW THE WARMER AIR TO MIX DOWN.
HIGH PRESSURE WILL MOVE OVERHEAD AS WELL. BUT SLIGHTLY WARMER TEMPERATURES ALOFT WILL OFFSET THAT TO A DEGREE. THE SNOW COVER AND SOUTHERLY FLOW ON THE BACKSIDE OF THE HIGH DO NOT SUPPORT GOOD MIXING.
NORTH WINDS WL CONTINUE TO SLOWLY BACK TOWARDS A MORE WESTERLY DIRECTION THIS EVENING AND OVERNIGHT AS A 1004 MB HIGH PRESSURE SYSTEM MOVES INTO THE REGION. THIS HIGH PRESSURE WILL INCREASE SUBSIDENCE AND CLEAR OUR SKIES. WITH SUSTAINED WINDS IN THE LOWER SINGLE DIGITS. ARCTIC HIGH PRESSURE WILL SWING THROUGH THE REGION FRIDAY TO OUR SOUTH. WINDS WL STRENGTHEN BY TOMORROW AFTN AS THE PRESSURE GRADIENT TIGHTENS AND CONTINUES TO BACK TOWARDS A MORE SOUTHWESTERLY DIRECTION AS THE HIGH PRESSURE MOVES OFF TO THE EAST.
WEAK FLOW ALOFT SETS UP ON FRIDAY WITH UPPER LEVEL LOW DROPPING INTO CALIFORNIA. LITTLE OR NO ENERGY OVER WYOMING WELL AHEAD OF THIS TROUGH.
MEANWHILE AREAS IN THE EAST ARE ACTUALLY COOLER THAN THOSE IN THE WEST AS THE THICKER STRATUS CLOUDS HAVE NOT ALLOWED TEMPERATURES TO GO FAR. TONIGHT WE WILL SEE ANOTHER LOBE OF ENERGY SLIDE AROUND THE BASE OF THE TROUGH IN THE EAST.
124 PM PST Thu Feb 26 2015 A weather system will move into the area on Friday, leading to cooler and wetter weather into the weekend.
ANOTHER STRONG COLD FRONT PUSHED SOUTH ACROSS THE FORECAST AREA YESTERDAY EVENING. WITH A STEEPLY SLOPED THERMAL GRADIENT IN THE LOW TO MID LEVELS. WITH ARCTIC AIR TRAPPED IN THE LOW LEVELS AND PROLONGED PERIODS OF STRONG OVER-RUNNING OF WARM MOIST AIR ACROSS KANSAS.
COLD HIGH PRESSURE SINKING SOUTHWARD THROUGH THE PLAINS WILL INCREASE THE DEPTH OF THE DENDRITIC GROWTH ZONE AND EXTEND IT INTO THE BOUNDARY LAYER ACROSS FAR SOUTHWEST KANSAS DURING THIS SHORT TERM PERIOD. COLD OVERNIGHT TEMPERATURES WILL RETURN TO THE SINGLE DIGITS ACROSS A BROAD AREA BY EARLY FRIDAY MORNING, AFTER PROBABLY NOT EXCEEDING THE LOW 20S ANYWHERE IN THE FORECAST AREA ON THURSDAY. STRONG WESTERLY FLOW ALOFT WILL DEVELOP FROM THE DESERT SOUTHWEST THROUGH THE CENTRAL PLAINS TOWARD THE GREAT LAKES REGION AS THE TROUGH DEVELOPS IN THE WEST AND FLAT RIDGING DEVELOPS OVER THE EASTERN STATES.
THIS WINDOW IS RATHER SMALL FOR ALL BUT THE RIDGES BEFORE SUBSIDENCE TAKES PLACE. ONLY ADDING ABOUT AN INCH TO THE HIGHEST ELEVATIONS OF PA/WV/MD. STAYED ON THE WARMER SIDE OF GUIDANCE AS EXPECT CLOUD COVER TO KEEP TEMPERATURES FROM BOTTOMING OUT. THE LOW WINDS EXPECTED WITH BUILDING HIGH PRESSURE SHOULD LIMIT ANY CONCERNS FOR WIND CHILL ADVISORIES OVERNIGHT. WITH HIGH PRESSURE OVERHEAD FRI NIGHT/SAT MORNING TEMPERATURES SHOULD DROP SIGNIFICANTLY ONCE AGAIN.
THE UPPER RIDGE OVER THE WEST WAS GETTING DEFORMED BY A SPLITTING PACIFIC TROUGH THAT WAS MOVING INLAND. SOME CLOUDS RETURN TO THE NORTH IN THE AFTERNOON AS ANOTHER BATCH OF MOISTURE TOPS THE RIDGE.
WITH FREEZING LEVELS RANGING FROM NEAR 2 KFT IN DEEP EAST TEXAS AND ADJACENT LOUISIANA. AS A POSITIVELY TILTED UPPER TROF MOVES ACROSS TX. AS THE TROF CONTINUES EWD AND THE MOISTURE SUPPLY BECOMES CUT OFF. /ISSUED 416 AM CST FRI JAN 23 2015/ COLD CORE UPPER TROUGH IS WELL WEST OF THE AREA BUT IT SHOULD MOVE ACROSS THE CWA THIS EVENING/TONIGHT. MOST OF THE ATMOSPHERE IS BELOW FREEZING WITH THE EXCEPTION OF THE LOWEST 2000 FEET OR SO AND SFC TEMPS ARE STILL AROUND 40 DEGREES F. ANY SNOW THAT MAY BE FALLING WILL MOST LIKELY MELT IN THIS LOWEST LAYER PRIOR TO REACHING THE SFC. BUT WITH SFC TEMPERATURES REMAINING ABOVE FREEZING NO ACCUMULATIONS AND NO IMPACTS ARE ANTICIPATED. OVERNIGHT LOWS ALONG AND NORTH OF I-20 WILL LIKELY BE NEAR OR BELOW FREEZING.
257 PM CST FRI JAN 23 2015 FIRST FORECAST CONCERN IS CLOUD TRENDS THIS EVENING INTO THE OVERNIGHT HOURS AND THE POTENTIAL FOR PATCHY FOG AND PERHAPS SOME LIGHT FREEZING DRIZZLE. ESPECIALLY ALONG RIDGE TOPS AND ACROSS THE ELEVATED TERRAIN OF SOUHEAST MINNESOTA/NORTHEAST IOWA. IF THE FOG DEVELOPS SOME LIGHT FREEZING DRIZZLE MAY ALSO OCCUR. CONFIDENCE LOW ON THE FREEZING DRIZZLE DEVELOPING SO HAVE NOT ADDED IT TO THE FORECAST. GIVEN THE LOW CONFIDENCE ON THE PLACEMENT OF THIS BAND WILL HOLD OFF ON ANY HEADLINES AT THIS TIME.
DRY AND WARMER WEATHER IS EXPECTED TODAY AND OVER THE WEEKEND.
942 AM MST Fri Jan 23 2015 Forecast area remains under a dry NW flow aloft downstream of an upper level ridge axis along the US West Coast. There will even be a small risk of brief freezing rain in the southwest valleys.
SURFACE ANALYSIS SHOWS A TROUGH OF LOW PRESSURE THAT HAS NEARLY MADE IT THROUGH THE FORECAST AREA AT THIS TIME. EXPECT AN INCREASE IN CLOUDS BUT WILL CONTINUE WITH A DRY FORECAST SINCE THE LOWER LEVELS ARE FAIRLY DRY AND WILL TAKE SOME TIME FOR THE LOWEST LAYER TO MOISTEN UP ENOUGH TO GET RAIN TO THE SURFACE. MODELS ARE SHOWING A CONSISTENT SIGNAL BREAKING DOWN THE RIDGE TO OUR WEST AND BRINGING A COLD FRONT ACROSS THE LOCAL AREA.
TEMPERATURES REMAIN ABOVE FREEZING IN THE 30S ACROSS ALL LOCATIONS.
/ISSUED 558 AM CST Fri Jan 23 2015/ /12Z TAFS/ An upper level low will move across the area today, resulting in MVFR/IFR conditions and light snow or a mix of light rain and snow at the terminals through 16Z. /ISSUED 500 AM CST Fri Jan 23 2015/ (Today and Tonight) Latest water vapor imagery shows the upper low near Midland early this morning. With surface temperatures remaining above freezing, snow accumulations will be limited to mainly grassy surfaces as well as bridges and overpasses. Precipitation will end around noon across eastern and southeast counties as the upper low moves off to the east.
1203 PM CST FRI JAN 23 2015 FREEZING RAIN AND SLEET HAS MOVED OUT OF THE AREA. WHILE TEMPS HAD ALREADY CLIMBED ABOVE FREEZING IN SOME AREAS. AND ROAD AND AIR TEMPS CLIMB ABOVE FREEZING. HIGHS ON SATURDAY WILL BE COOLER BUT STILL IN THE UPPER 20S TO MIDDLE 30S.
WARMER TEMPS ARE EXPECTED SATURDAY WITH HIGHS MOSTLY IN THE 50S.
WARMER HIGH TEMPERATURES TODAY WITH WARMUP TO CONTINUE THIS WEEKEND.
230 PM MST FRI JAN 23 2015 SATELLITE AND UPPER AIR ANALYSIS INDICATE NORTHERLY UPPER LEVEL FLOW OVER THE PLAINS DUE TO A RIDGE OVER THE WEST COAST AND A TROUGH OVER SOUTHEAST CANADA. A BAND OF MIDLEVEL CLOUDS WAS PRESENT IN THE FLOW AHEAD OF A SHORT WAVE TROUGH. TONIGHT AND SATURDAY DRY AND WARMER CONDITIONS CAN BE EXPECTED DUE TO THE DRY NORTHERLY FLOW AND WAA.
Ridging will then squeeze into the central and eastern Plains ahead of a quickly approaching clipper system, allowing winds to return to the west southwest and temperatures to climb into the 50s area-wide tomorrow afternoon.
TEMPERATURES RIGHT AROUND FREEZING WITH DOT INDICATING ROAD SURFACE TEMPERATURES ABOVE FREEZING OVER SE ND. WILL BE SEEING VERY MILD START MOST AREAS AND WHILE COLUMN DOES COOL WE SHOULD STILL SEE MAXIMUM TEMPERATURES ABOVE FREEZING. LACK OF SNOW COVER WILL ALLOW FOR SOME SLIGHT WARMING WITH MOST AREAS GETTING TO OR ABOVE FREEZING.
RAIN WILL CONTINUE TO PUSH EAST OF THE AREA THIS AFTERNOON AS UPPER TROUGH SWINGS THROUGH AND DRIER AIR MOVES IN FROM THE NORTH/WEST. EXPECT TEMPS TO FALL INTO THE 30S YET CONCUR WITH SREF PROBABILITIES THAT READINGS WILL REMAIN ABOVE FREEZING.
320 PM EST FRI JAN 23 2015 WARMER TEMPERATURES TONIGHT AND SATURDAY AHEAD OF CANADIAN LOW PRESSURE SYSTEM MOVING ACROSS CENTRAL QUEBEC. THE NORTH COUNTRY WILL BE SANDWICHED BETWEEN THIS LOW AND A COASTAL LOW ON SATURDAY, RESULTING IN LIGHT SNOW AFFECTING CENTRAL AND EASTERN VERMONT FROM THE COASTAL LOW AND SNOW SHOWERS SPREADING FROM NORTHERN NEW YORK INTO EASTERN VERMONT LATER IN THE DAY SATURDAY.
THE BETTER CHANCES FOR ANY RAINFALL WILL BE OVER SOUTHWEST MINNESOTA THIS MORNING AND WITH TEMPERATURES AT OR BELOW FREEZING SOME SLICK ROADS WILL BE POSSIBLE. WITH VERY DRY AIR IN THE LOWER PART OF THE ATMOSPHERE NOT ANTICIPATING MUCH IF ANY MEASURABLE RAINFALL.
EXPECT TEMPS TO FALL INTO THE 30S YET CONCUR WITH SREF PROBABILITIES THAT READINGS WILL REMAIN ABOVE FREEZING.
A WARM FRONT WILL MOVE THROUGH WASHINGTON LATE TODAY AND OVERNIGHT BRINGING SOME LIGHT RAIN TO THE STATE AS WELL AS CLIP NORTHERN OREGON. A DECK OF STRATUS AND FOG WILL PERSIST THROUGHOUT THE LOWER COLUMBIA BASIN. CENTRAL OREGON WILL REMAIN DRY AND WARM AS THE WARM FRONT BRINGS WARMER AIR INTO THE REGION.
SURFACE ANALYSIS HAD THE LOW JUST SOUTH OF THE FLORIDA PANHANDLE. LIGHT RAIN AND LIGHT DRIZZLE WILL CONTINUE OVER OUR CWA AHEAD OF AN APPROACHING UPPER LEVEL TROUGH THAT WAS NOTED OVER THE SOUTHERN PLAINS THIS MORNING. BUFR SOUNDINGS CONTINUE TO SHOW SOME POSSIBILITY OF LIGHT SNOW MIXING IN WITH THE LIGHT RAIN ALONG THE HIGHWAY 82 CORRIDOR BEFORE ALL THE PRECIPITATION COMES TO AN END AFTER MIDNIGHT. MAX TEMPS SHOULD BE MAKE IT INTO THE LOW TO MID 50S.
UPPER LEVEL TROUGH AXIS WILL SHIFT EAST OF THE AREA TONIGHT INTO SATURDAY MORNING. A FEW LOCATIONS ACROSS THE NORTHERN ZONES MAY APPROACH FREEZING AND WILL REISSUE SPS TO HIGHLIGHT THE COLDER TEMPERATURES. WITH TEMPS IN THE LOWER/MIDDLE 60S. NOT AS COLD TOMORROW NIGHT WITH LOWS IN THE LOWER 40S.
ALLOWED THE PORTION OF THE WINTER WEATHER ADVISORY TO EXPIRE ACROSS THE NORTH WHERE FREEZING PRECIP HAS WELL SINCE ENDED AND REPORTS OF IMPROVING ROAD CONDITIONS HAVE BEEN RECEIVED. WHILE TEMPS HAD ALREADY CLIMBED ABOVE FREEZING IN SOME AREAS. AND ROAD AND AIR TEMPS CLIMB ABOVE FREEZING. HIGHS ON SATURDAY WILL BE COOLER BUT STILL IN THE UPPER 20S TO MIDDLE 30S.
250 PM MST FRI JAN 23 2015 HERE TO THE SOUTHEAST OF THE AMPLIFYING RIDGE. THIS ONE IS WEAKER AS THE RIDGE BULGES INLAND PRODUCING WARM ADVECTION.
AN UPPER LEVEL TROUGH OVER THE NORTHERN ROCKIES WILL DIVE SOUTH- SOUTHEAST ACROSS THE CENTRAL ROCKIES TODAY AND INTO THE SOUTHERN ROCKIES TONIGHT. TEMPERATURES WILL BE WARMER THAN YESTERDAY DUE TO A WARMER START AND A WARMER AIRMASS IN PLACE. EXPECT HIGHS TO MAINLY BE IN THE LOWER 40S OVER NORTHEAST COLORADO. WEAK RIDGING WILL REBUILD OVER THE AREA LATE TONIGHT BRINGING CLEARING SKIES LATE TONIGHT. MOVING INTO A TRANQUIL PERIOD OF JANUARY THAW WEATHER BEGINNING SATURDAY WITH A STRONG UPPER LEVEL RIDGE OF HIGH PRESSURE SLOWLY MIGRATING ACROSS THE REGION.
SNOW COVER ACROSS THE LOWER ELEVATIONS CONTINUES TO MELT WITH A SMORGASBORD OF TEMPERATURES IN THE 20S. WITH SOME LIGHT SNOW OR FLURRIES POSSIBLE ACROSS THE HIGHER PEAKS. WITH INDUCED LEE TROUGHING ACROSS THE EASTERN PLAINS AND WARMING ALOFT AHEAD OF THE SYSTEM. TEMPERATURES WILL CONTINUE WARM AREAWIDE WITH AT AND ABOVE SEASONAL HIGHS IN THE MID 40S TO MID 50S EXPECTED ACROSS THE EASTERN PLAINS AND MAINLY 30S AND 40S ACROSS THE HIGHER TERRAIN.
A few locations may even cool into the lower 20s, especially in any river valleys or near area lakes. (Saturday night through through Friday) West Central Texas will be situated between two upper-level troughs this weekend; one progressive trough moving southeast across the Plains and a broad, cut-off cyclone retrograding very slowly to the west over the Baja Peninsula. In the vicinity of the deformation zone between the aforementioned troughs, we'll see light winds aloft and generally weak westerly low-level winds Saturday night.
GULF LOW PRESSURE OVER THE AREA TODAY HAS RESULTED IN PERSISTENT LIGHT RAIN. THIS LOW IS EXPECTED TO LIFT NORTHEASTWARD OVERNIGHT. THE BEST CHANCES FOR SNOW AND SNOW ACCUMULATIONS WILL BE IN THE HIGHER ELEVATIONS OF NORTH GEORGIA /GENERALLY ABOVE 1500 FEET/. WITH SURFACE TEMPERATURES LARGELY REMAINING ABOVE FREEZING THROUGH SATURDAY MORNING. 5 INCH ACCUMULATIONS IN THE HIGHER ELEVATIONS. FOR ISOLATED LOCATIONS IN FAR NORTH GEORGIA WHERE THE TEMPERATURES DROP BELOW FREEZING.
WITH THE COLDEST AIR ALONG THE LOWER ARK RVR VALLEY FROM PUEBLO TO THE CO/KS BORDER. EXPECT TEMPS GENERALLY IN THE U30S TO A FEW M40S ACROSS THE LOWER ELEVATIONS TODAY. LOWS TONIGHT WILL BE WARMER THAN THIS MORNINGS LOW DUE TO THE WINDS KEEPING UP A BIT TONIGHT AND CLOUDS OVER THE REGION.
AS A S/W TROF AND THE RRQ OF AN UPPER JET IMPACT THE REGION. AND TEMPERATURES SHOULD RISE TO A LITTLE ABOVE FREEZING. SOME PATCHY FREEZING DRIZZLE MAY LINGER INTO THE EARLY EVENING AS REMAINING PCPN TAPERS OFF.
1220 PM EST FRI JAN 23 2015 HIGH PRESSURE OVER THE REGION WILL BE DISPLACED AS A TROUGH OF LOW PRESSURE DEVELOPS INTO EASTERN KENTUCKY TODAY AND THEN SUBSEQUENTLY MOVES OFF TO THE EAST TONIGHT.
THEREFORE CONTINUED TO FOLLOW THE WARMER GUIDANCE VALUES FOR LOWS TONIGHT WHICH WERE GENERALLY THE ECMWF AND GEM BIAS CORRECTED READINGS.
By and large, the forecast period will be dominated by a ridge west/trof east pattern across North America, a pattern that has been pretty common of late.
318 PM CST FRI JAN 23 2015 A NORTHWEST FLOW ALOFT WILL DEVELOP BEHIND THE UPPER LEVEL TROUGH CURRENTLY MOVING ACROSS SE TEXAS THIS AFTERNOON.
235 PM EST FRI JAN 23 2015 HIGH PRESSURE AND FAIR SKIES THIS AFTERNOON WILL GIVE WAY TO INCREASING CLOUDS. SYSTEM IS ABLE TO TAP THE DEEP MOISTURE FROM THE GULF SO A PD OF MOD SNOW SEEMS LIKELY OVER THE SE ZONES AHD OF THE UPR TROF. NARROW RDG BHD THE LOW FLATTENS OUT SAT AFTN AND EARLY SUN ALLOWING A NW FLOW OF CAA OFF THE LAKES.
1040 AM MST Fri Jan 23 2015 AVIATION SECTION UPDATED Forecast area remains under a dry NW flow aloft downstream of an upper level ridge axis along the US West Coast.
AN EXAMINATION OF FREEZING LEVELS THAT SUPPORTS SNOWFALL INDICATES THAT THE DEEPER MOISTURE WILL RESIDE WITH THE REQUIRED FREEZING LEVELS SOMETIME BETWEEN 03Z AND 06Z ACROSS THE PLATEAU. SUFFICIENT FREEZING LEVELS FOR SNOWFALL WILL BE REACHED SO THAT SNOW WILL REMAIN IN THE FORECAST. OVERNIGHT LOW TEMPERATURES TONIGHT WILL RANGE FROM THE UPPER 20S NORTH TO NEAR FREEZING SOUTHWEST. ALONG WITH WARMER TEMPS.
337 PM CST FRI JAN 23 2015 SUNNY SKIES ARE MAKING THINGS QUITE BRIGHT OUT THERE THIS AFTERNOON WITH TEMPERATURES RANGING FROM BELOW FREEZING AT LOCATIONS THAT RECEIVED THE HEAVIEST SNOWFALL YESTERDAY TO THE BALMY MID 40S ACROSS THE SNOW-LESS GROUND IN BEAVER COUNTY OKLAHOMA.
This will occur as a trough of low pressure approaches from the northwest today which in essence is further attached to an area of low pressure tracking east through south-central Canada. Developing southwest downslope flow combined with an approaching thermal ridge in advance of the trough should allow temps to warm well above normal this afternoon with low 50s likely along and west of I-35.
/ISSUED 529 AM CST Fri Jan 23 2015/ Issued update to extend the Winter Storm Warning and Winter Weather Advisory across eastern and central portions of the Permian Basin, the Western Low Rolling Plains, and the Lower Trans Pecos through 9 am CST. /ISSUED 415 AM CST Fri Jan 23 2015/ Snow continues to move across the Permian Basin and the Trans Pecos this morning with temperatures near or below freezing. The upper trough that is over the region and contributing to the snow is expected to move over eastern TX this afternoon. A broad upper trough will be over the eastern conus and Upper Midwest with a closed low taking shape off the coast of Mexico south of California beginning on Saturday.
1131 AM CST Fri Jan 23 2015 An upper level trough is currently located across western Texas early this morning and will track east into the Gulf coast states by tonight. Warmer conditions will occur this weekend as highs warm into the 50 both afternoons.
AND VARYING AMOUNTS OF STRATUS AND FOG IN THE HIGHER VALLEYS AND BASINS.
346 PM EST FRI JAN 23 2015 MAIN FOCUS FOR THIS FORECAST PACKAGE REMAINS THE THUNDERSTORM POTENTIAL OVERNIGHT TONIGHT AND INTO SATURDAY MORNING AND SUBSEQUENT COOLER THAN NORMAL WEEK AHEAD. THIS IS DRIVEN BY A HIGHLY AMPLIFIED POSITIVELY TILTED H5 TROUGH AXIS POSITIONED ROUGHLY ACROSS THE ARKLATEX. THIS WILL DRIVE A COLD FRONT THROUGH THE AREA DURING THE DAY SATURDAY. A MUCH COOLER AND DRIER AIR MASS IS THEN EXPECTED TO FILTER INTO SOUTH FLORIDA WITH A COOL CONTINENTAL NORTH-NORTHWESTERLY SURFACE FLOW.
AN UPPER LEVEL TROUGH WILL PROGRESS EASTWARD, AWAY FROM KANSAS TODAY AND TONIGHT. TEMPERATURES WILL CONTINUE A GRADUAL WARMING TREND TODAY, WITH SUNNY SKIES AND WESTERLY DOWNSLOPE FLOW LEADING TO WARMER HIGHS IN THE UPPER 40S TO LOWER 50S. ON THE HIGH PLAINS, IT ONLY TAKES A BRIEF DROP OFF IN WINDS AT NIGHT FROM 10 TO 5 KTS TO RESULT IN A SHORT-LIVED, DOWNWARD SPIKE IN TEMPERATURES. THIS WAVE PUSHES A COLD FRONT SOUTH THROUGH THE CENTRAL PLAINS SATURDAY NIGHT.
AN UPPER LOW. EAST OF THE LOW. COLDER AIR MOVING TO THE SE INTO THE DEEPENING CYCLONE WILL RESULT IN THE RAIN ENDING FROM WEST TO EAST DURING THE OVERNIGHT AND SATURDAY MORNING. SEASONABLY MOSTLY CLEAR AND COLD SATURDAY NIGHT WITH LOWS IN THE LOWER 30S.
321 PM CST FRI JAN 23 2015 UPPER LOW OVER TX IS THE PROMINENT FEATURE IN THE WV IMAGERY. THE TROF WILL CONTINUE TO PUSH EWD TONIGHT. NW FLOW ALOFT WILL OVERTAKE THE LOWER MS VALLEY AS WE MOVE INTO SATURDAY. WITH THE UPPER RIDGE REMAINING ANCHORED OVER THE WRN U.
1107 AM CST FRI JAN 23 2015 AN UPPER LOW CAN BE SEEN ON THE LATEST SATELLITE IMAGERY TRANSLATING EAST ACROSS THE REGION. /ISSUED 436 AM CST FRI JAN 23 2015/ THE UPPER LOW RESPONSIBLE FOR OUR PRECIPITATION EVENT WILL SWING THROUGH THE REGION TODAY. THE FROZEN HYDROMETEORS FULLY MELTED IN THE 2000FT LAYER ADJACENT TO THE GROUND THAT REMAINS ABOVE FREEZING. THE PRECIPITATION TODAY WILL BE ASSOCIATED WITH THE LARGE-SCALE LIFT APPROACHING WITH THE 500MB TROUGH. ANY SNOW WOULD POSE NO SIGNIFICANT IMPACTS TO TRAVEL AS SURFACE TEMPERATURES REMAIN ABOVE FREEZING. RIDGING WILL THEN BUILD INTO THE GREAT BASIN.
TODAY THROUGH SATURDAY NIGHT 09Z SURFACE ANALYSIS HAD WEAK TROUGH FROM NORTHWEST MN INTO CENTRAL WY. UPPER RIDGE CONTINUES TO DOMINATE THE WEATHER OVER THE WESTERN THIRD OF THE COUNTRY. LOW PRESSURE WILL FOLLOW THIS TRACK.
STRONG HIGH PRESSURE WILL BUILD IN DURING THE WEEKEND.
VERTICAL TEMPERATURE PROFILES ARE FORECAST TO REMAIN ABOVE FREEZING THIS AFTERNOON. THE MAIN UPPER LEVEL TROUGH. AS THE NEW GUIDANCE IS STILL SUPPORTIVE OF LIGHT SNOW ACROSS THE HIGHER ELEVATIONS. HOWEVER GIVEN THE LOW COVERAGE.
), with another band of mid level cloudiness dropping southeast across the area overnight as surface trof/weak cold front drops into the region.
AS TEMPERATURES BEHIND IT ARE PROGRESSIVELY WARMER THAN AHEAD OF IT DUE TO THE DOWNSLOPING EFFECT. ESPECIALLY THE HIGH RESOLUTION NAM/RAP/HRRR SOLUTIONS. SKIES OVER THE ENTIRE GENERATION REGION REMAIN CLEAR AS A BELL AT THIS HOUR AND THE HIGH RES MODELS WERE EARLIER DEVELOPING THE CLOUDS EVEN BY THIS TIME.
A VIGOROUS SHORT WAVE TROUGH IS PRESSING EAST ACROSS THE RED RIVER VALLEY. A STRENGTHENING LOW PRESSURE TROUGH EXTENDS SOUTHWEST FROM THE WESTERN FLORIDA PENINSULA. AHEAD OF THE TROUGH. AN AREA OF LOW PRESSURE DEVELOPING ACROSS THE WESTERN GULF OF MEXICO WILL MOVE EAST-NORTHEASTWARD THIS AFTERNOON THROUGH SATURDAY. AN ASSOCIATED COLD FRONT WILL PASS THROUGH THE FLORIDA KEYS AND AREA COASTAL WATERS ON SATURDAY. A FEW LIGHT SHOWERS NEAR THE LOWER KEYS MAY CROSS THE ISLAND CHAIN. THE HIGH TEMPERATURE IN KEY WEST HIT 86 DEGREES.
A PROGRESSIVE MID/UPPER LEVEL TROUGH WAS LAID OUT FROM TX TO IA EARLY THIS MORNING. BEFORE ONE MORE ROUND OF PRECIP MOVES THROUGH FROM NW TO SE TONIGHT ALONG/AHEAD OF THE MID/UPPER LEVEL TROUGH AXIS. LATEST MODEL DATA SUGGESTS A PERIOD OF SNOW OR RAIN/SNOW MIX WITH TEMPS JUST ABOVE FREEZING UNTIL COLDER AIR MAKES ITS WAY IN TONIGHT. THE MOST LIKELY PLACE TO SEE SOME LIGHT ACCUMULATION WILL BE ON RIDGES. PERIOD WILL BEGIN WILL LOW PRESSURE THAT AFFECTED MUCH OF THE REGION WELL NORTH NEAR THE MAINE COAST. THERE WILL BE SOME BRIEF RIDGING AHEAD OF NEXT DISTURBANCE.
AN AREA OF LOW PRESSURE OVER THE SOUTHEAST U. WILL MOVE OFF THE MIDDLE ATLANTIC COAST SATURDAY AS A HIGH PRESSURE RIDGE ACROSS OUR AREA WEAKENS.
323 PM EST FRI JAN 23 2015 HIGH PRESSURE MOVES OFFSHORE TONIGHT. THIS GIVES WAY TO LOW PRESSURE MOVING UP THE COAST. THIS LOW WILL BRING A PERIOD OF SNOW SATURDAY AND SATURDAY EVENING BEFORE EXITING INTO THE MARITIMES SATURDAY NIGHT.
A LOW PRESSURE SYSTEM TRACKING THROUGH THE SOUTHERN APPALACHIAN REGION WILL KEEP LOW CLOUDS AND REDUCED VIS FOR MVFR TO IFR CONDITIONS IN PLACE THROUGH AT LEAST 12Z TO 15Z SAT.
THIS EVENING THROUGH SATURDAY NIGHT CURRENT SURFACE ANALYSIS SHOWS HIGH PRESSURE OVER THE NORTHERN ROCKIES WITH A NE-SW TROUGH OVER MINNESOTA IOWA AND NEBRASKA. THE UPPER ANALYSIS INDICATES RIDGING OVER THE WEST COAST WITH AN UPPER LOW OVER TEXAS. THE UPPER RIDGE WILL REMAIN OVER THE WEST COAST. TEMPERATURES WILL BE NEAR GUIDANCE AND CONTINUED WARMER THAN AVERAGE.
LIGHT SNOW BECOMING FREEZING RAIN ACROSS NORTHWEST MONTANA. STRONG VALLEY TEMPERATURE INVERSIONS AND STAGNANT AIR ACROSS A weak and relatively warm Pacific storm system will impact the Northern Rockies with light snow becoming freezing rain this evening through midday Saturday.
1255 PM EST FRI JAN 23 2015 HIGH PRESSURE OVER THE OHIO VALLEY/LOWER GREAT LAKES WILL MOVE OFF THE MID ATLANTIC COAST LATE TODAY. A COLD FRONT WILL MOVE ACROSS THE EASTERN LAKES SATURDAY.