Aikyam-Lab/Synoptic-Bench huggingface dataset:
656 PM EST FRI FEB 27 2015 CANADIAN HIGH PRESSURE WILL BUILD INTO THE AREA OVER THE WEEKEND WITH TEMPERATURES REMAINING BELOW NORMAL. HIGH PRESSURE WILL EXTEND FROM THE OHIO VALLEY TO MID-ATLANTIC REGION TONIGHT. WIND ASSOCIATED WITH HIGH PRESSURE BUILDING NORTH OF THE REGION SHOULD HELP PREVENT FOG TONIGHT DESPITE HIGH LOW-LEVEL MOISTURE FROM THE RECENT RAIN EVENT. THE WARMER LOW TEMPERATURE GUIDANCE MAY VERIFY BECAUSE OF WIND. BUT WE KEPT THE FORECAST CONSISTENT AND LEANED TOWARD THE COOLER MAV MOS BECAUSE OF THE COLD AIR AND SNOW COVER UPSTREAM. THERE IS SOME POSSIBILITY OF LIGHT FREEZING RAIN ACROSS THE NORTH MIDLANDS. CONFIDENCE REMAINS LOW SO ONLY INDICATED A SLIGHT CHANCE FOR LIGHT FREEZING RAIN.
MIN TEMPS MAY BE A BIT WARMER THAN FORECASTED GIVEN INCREASING CIRRUS. RETURN FLOW WILL CONTINUE AND TEMPS WILL BE WARMER THAN PAST NIGHTS.
A FEW FLURRIES STILL POSSIBLE MAINLY NEAR THE COLORADO BORDER THIS EVENING DUE TO THE UPSLOPE PATTERN INDUCED BY THE CHEYENNE RIDGE. EXPECT TO SEE LIGHT SNOW INCREASE FROM THE SW AGAIN LATE SATURDAY AS AN IMPULSE RIDES ENE FROM AN UPPER LOW ALONG THE CALIFORNIA COAST AND SFC UPSLOPE STEPS UP A BIT IN RESPONSE TO AN INCREASING SFC PRESSURE GRADIENT MAINLY ACROSS SRN WY.
1026 PM EST FRI FEB 27 2015 CURRENTLY - A LARGE HIGH PRESSURE SYSTEM IS MOVING EASTWARD THROUGH THE EASTERN UNITED STATES. GOOD VEERING THROUGH THE LOWER LEVELS IN AN ALREADY MOIST ENVIRONMENT IS RESPONSIBLE FOR MOSTLY CLOUDY SKIES AND FOR THE DEVELOPMENT OF A FEW SWATHS OF LIGHT RAIN OR SPRINKLES. THE VEERING FLOW WILL ALSO BRING IN A WARMER AIRMASS. A LARGE HIGH PRESSURE SYSTEM OVER THE EASTERN UNITED STATES IS RESPONSIBLE FOR FRESH NORTHEAST BREEZES ACROSS ALL KEYS WATERS TONIGHT. WINDS WILL GRADUALLY TRANSITION EAST NORTHEAST OVERNIGHT AS THE HIGH CONTINUES TO DRIVE EASTWARD. AMPLE MOISTURE WITH DECENT VEERING AT LEAST IN THE LOW LEVELS MAY PRODUCE SPRINKLES TO PERIODS OF LIGHT RAIN TONIGHT.
552 PM CST Fri Feb 27 2015 Strong 1040 mb arctic high pressure near the IA/MO/IL border projected by latest forecast models to strengthen to 1045 mb as it moves east to northern PA by 12Z/6 am Sat and mid Atlantic states by 18Z/noon Sat. High pressure ridge still ridging back west into central/northern IL through midday Saturday.
THE SOUTH END OF THIS SYSTEM WILL MOVE INTO MUCH DRIER AIR AND BECOME MOISTURE STARVED TONIGHT AND ON SATURDAY WHILE KANSAS PART OF THIS SYSTEM HEADS ACROSS MISSOURI DURING THE DAY ON SATURDAY IN THE FORM OF SNOW WITH THE POTENTIAL FOR SOME FREEZING RAIN.
HOWEVER, WITH SNOW COVER STILL PRESENT ACROSS PORTIONS OF THE TN VALLEY (AND SOURCE REGION OF COLD ARCTIC AIRMASS) STILL EXPECTING TEMPS TO DROP BELOW FREEZING. THEN, THE UPPER LEVEL PATTERN BEGINS TO SHIFT WITH THE SHEARED TROUGH AXIS (JET STREAK) OVER THE EASTERN PART OF THE COUNTRY MOVING OFF TO THE NORTHEAST WHILE THE WEST COAST JET STREAK BEGINS TO AMPLIFY INTO A TROUGH AND GAINS A POSITIVE TILT.
TEMPERATURES AT THE AIRPORTS SHOULD REMAIN JUST ABOVE FREEZING AND WILL NOT MENTION FZDZ AT THIS TIME. TEMPERATURES HAVE REMAINED BELOW FREEZING IN THE HILL COUNTRY AND ALONG THE ESCARPMENT AREAS WITH SOME REPORTS OF LIGHT FREEZING RAIN/DRIZZLE. BRIDGES AND OVERPASSES. TEMPERATURES WILL INCREASE ABOVE THE COLD DOME AT THE SURFACE WHICH IN TURN WILL WARM TO ABOVE FREEZING AS RAIN BRINGS DOWN THE WARMER AIR FROM ALOFT WITH PRECIPITATION TRANSITIONING TO ALL RAIN LATE TONIGHT INTO EARLY SATURDAY MORNING.
/ISSUED 340 PM CST FRI FEB 27 2015/ LONGWAVE UPPER LEVEL TROUGH IS CURRENTLY IN PLACE OVER NORTH AMERICA WITH AN ARCTIC HIGH CENTERED OVER MISSOURI. WHICH WOULD ALLOW FOR A CHANGE OVER TO FREEZING RAIN.
THE UPPER LOW ALONG THE PACIFIC NORTHWEST COAST WILL DROP SOUTH TONIGHT AND INTO CENTRAL CALIFORNIA SATURDAY AFTERNOON. AHEAD OF THE LOW.
A CLEAR SKY AND LIGHT WIND FIELD WILL EXIST OVERNIGHT AND INTO SATURDAY UNDER THE INFLUENCE OF STRONG HIGH PRESSURE AND A DEEP DRY LAYER.
CHATTANOOGA AIRPORT, TN 27 45 34 50 / 0 10 10 30 KNOXVILLE MCGHEE TYSON AIRPORT, TN 22 41 33 50 / 0 10 10 20 OAK RIDGE, TN 22 42 34 50 / 0 10 10 20 TRI CITIES AIRPORT, TN 18 39 30 50 / 10 10 0 20.
207 PM PST Fri Feb 27 2015 A weather system will move across California this weekend, leading to cooler and wetter weather.
Expect periods of -FZDZ to persist through Saturday morning, potentially resulting in slick runways during this time as temps remain well below freezing through mid-day. Road conditions were certainly affected earlier today by significant snowfall combined with some light freezing precipitation. As this occurs, we will see a transition from light snow to light freezing drizzle. In addition, areas of freezing fog are expected to develop along and east of the mountains as well. While we are not anticipating significant accumulations of ice, there is certainly potential for minor ice accumulations that will affect bridges and overpasses. We should finally see a warmup beginning late tomorrow afternoon as we finally warm above freezing into the 40s.
817 PM EST FRI FEB 27 2015 STRONG HIGH PRESSURE WILL BUILD NORTH OF THE REGION TONIGHT. A COASTAL TROUGH IS EXPECTED TO DEVELOP IN THIS FLOW TONIGHT. TO THE LOWER 50S COASTAL NORTHEAST FLORIDA.
EXPECT PERIODS OF -FZDZ TO PERSIST THROUGH SATURDAY MORNING, POTENTIALLY RESULTING IN SLICK RUNWAYS DURING THIS TIME AS TEMPS REMAIN WELL BELOW FREEZING THROUGH MID-DAY. ROAD CONDITIONS WERE CERTAINLY AFFECTED EARLIER TODAY BY SIGNIFICANT SNOWFALL COMBINED WITH SOME LIGHT FREEZING PRECIPITATION. AS THIS OCCURS, WE WILL SEE A TRANSITION FROM LIGHT SNOW TO LIGHT FREEZING DRIZZLE. IN ADDITION, AREAS OF FREEZING FOG ARE EXPECTED TO DEVELOP ALONG AND EAST OF THE MOUNTAINS AS WELL. WHILE WE ARE NOT ANTICIPATING SIGNIFICANT ACCUMULATIONS OF ICE, THERE IS CERTAINLY POTENTIAL FOR MINOR ICE ACCUMULATIONS THAT WILL AFFECT BRIDGES AND OVERPASSES. WE SHOULD FINALLY SEE A WARMUP BEGINNING LATE TOMORROW AFTERNOON AS WE FINALLY WARM ABOVE FREEZING INTO THE 40S.
TEMPERATURES WILL GENERALLY REMAIN IN THE 50S ACROSS THE AREA WITH THE LOW CLOUDS IN PLACE.
510 PM CST FRI FEB 27 2015 AN AREA OF HIGH PRESSURE AND DRY AIR WILL KEEP THE NORTHLAND PRECIP FREE THROUGH MUCH OF THE SHORT TERM PERIOD. CLOUDS WILL GRADUALLY INCREASE FROM WEST TO EAST THROUGH THE DAY SATURDAY AS A TROUGH MOVES TOWARD THE NORTHLAND.
SATELLITE SHOWS UPPER LOW CENTERED OVER WESTERN OREGON THIS EVENING. THE LOW WILL MOVE SOUTH OVERNIGHT INTO CALIFORNIA AND NEVADA ON SATURDAY. RAIN AND HIGHER ELEVATION SNOW WILL GRADUALLY MOVE SOUTH WITH THE LOW. SIGNIFICANTLY COOLER TOMORROW AS COMPARED TO THE PAST SEVERAL DAYS. UPPER RIDGE OVER THE AREA SATURDAY NIGHT WITH CLEAR SKIES AND LIGHT WINDS.
A solid 4 - 6 inches on the ground there should keep low temps on the low side, which matches the MAV guidance pretty good. Initial thoughts are around 3-5" of snow across the northern CWA and about 1-3" across the southern CWA plus a light glaze of ZR and sprinkling of IP at times across the southern half when warmer air spreads northward on Sun morning. Quasizonal flow aloft becomes swly aloft on Sun/Mon after a piece of the large cutoff low over CA/Baja CA ejects ewd in response to an upstream kicker trof. Marked warmup on Tue-- highs reach mid to upper 50s on the warm side of the warm front.
1035 PM EST FRI FEB 27 2015 CANADIAN HIGH PRESSURE WILL BUILD INTO THE AREA OVER THE WEEKEND WITH TEMPERATURES REMAINING BELOW NORMAL. HIGH PRESSURE WILL EXTEND FROM THE OHIO VALLEY TO MID-ATLANTIC REGION TONIGHT. WIND ASSOCIATED WITH HIGH PRESSURE BUILDING NORTH OF THE REGION SHOULD HELP PREVENT FOG TONIGHT DESPITE HIGH LOW-LEVEL MOISTURE FROM THE RECENT RAIN EVENT. THE WARMER LOW TEMPERATURE GUIDANCE MAY VERIFY BECAUSE OF WIND. BUT WE KEPT THE FORECAST CONSISTENT AND LEANED TOWARD THE COOLER MAV MOS BECAUSE OF THE COLD AIR AND SNOW COVER UPSTREAM. THERE IS SOME POSSIBILITY OF LIGHT FREEZING RAIN ACROSS THE NORTH MIDLANDS. CONFIDENCE REMAINS LOW SO ONLY INDICATED A SLIGHT CHANCE FOR LIGHT FREEZING RAIN.
AS THE AREA REMAINS UNDER THE INFLUENCE OF HIGH PRESSURE CENTERED OVER ILLINOIS. STRONG NORTHEAST WINDS WILL CONTINUE INTO SATURDAY WITH THE INFLUENCE OF THE HIGH PRESSURE TO THE NORTH AND NO CHANGES TO THE ON-GOING SMALL CRAFT ADVISORY AT THIS TIME. /ISSUED 255 PM CST FRI FEB 27 2015/ MID-AFTERNOON SFC ANALYSIS SHOWS HIGH PRESSURE IN PLACE OVER THE MIDWEST RIDGING SSWWD OVER THE FORECAST AREA. DRY WEATHER WILL PERSIST TONIGHT AND TOMORROW AS THE HIGH PRESSURE HOLDS ITS GRIP ON THE RIDGING WHILE SLIDING EWD. THIS WILL ALSO ALLOW FOR ONE MORE COOL NIGHT WITH MINS TONIGHT DROPPING TO THE FREEZING MARK OVER PORTIONS OF OUR NRN ZONES. WITH THE HIGH TAKING UP A MORE EWD POSITION TOMORROW LOW-LEVEL FLOW WILL TURN MORE ERLY WHICH WILL ALLOW MOISTURE TO BEGIN INCREASING OVER THE WRN GULF REGION.
536 PM CST FRI FEB 27 2015 COLD ARCTIC HIGH PRESSURE BEGINNING TO SLIDE AWAY FROM THE STATE TONIGHT.
/ISSUED 255 PM CST FRI FEB 27 2015/ MID-AFTERNOON SFC ANALYSIS SHOWS HIGH PRESSURE IN PLACE OVER THE MIDWEST RIDGING SSWWD OVER THE FORECAST AREA. DRY WEATHER WILL PERSIST TONIGHT AND TOMORROW AS THE HIGH PRESSURE HOLDS ITS GRIP ON THE RIDGING WHILE SLIDING EWD. THIS WILL ALSO ALLOW FOR ONE MORE COOL NIGHT WITH MINS TONIGHT DROPPING TO THE FREEZING MARK OVER PORTIONS OF OUR NRN ZONES. WITH THE HIGH TAKING UP A MORE EWD POSITION TOMORROW LOW-LEVEL FLOW WILL TURN MORE ERLY WHICH WILL ALLOW MOISTURE TO BEGIN INCREASING OVER THE WRN GULF REGION.
THE UPPER RIDGE AND OFFSHORE FLOW WILL BRING SUNNY DAYS AND COOL NIGHTS THIS WEEKEND.
MOISTURE RETURNING AT THE LOWER/UPPER LEVELS WILL HELP TO KEEP CLOUDS OVER SE TX THRU THIS UPCOMING WEEKEND AS TEMPS WARM AND PCPN CHCS INCREASE. AND AGAIN NEXT WEDS WITH THE PASSAGE OF A COLD FRONT.
/ISSUED 312 PM PST FRI FEB 27 2015/ THE UPPER LOW ALONG THE PACIFIC NORTHWEST COAST WILL DROP SOUTH TONIGHT AND INTO CENTRAL CALIFORNIA SATURDAY AFTERNOON. AHEAD OF THE LOW.
THE LATEST RAP13 AND NAM12 BOTH KEEP SURFACE WET BULB TEMPERATURES ABOVE FREEZING EXCEPT MAYBE ALONG THE FAR NORTHWEST BORDERS OF BURLESON. THIS WILL BE DETERMINED BY HOW CLOSE THE DRIZZLE AREA AND FREEZING TEMPERATURES CAN MOVE IN FROM WEST.
A MASSIVE AREA OF ARCTIC HIGH PRESSURE HAS SPREAD ACROSS THE COUNTRY FROM THE PLAINS TO THE EAST COAST NEAR THE CONFLUENCE ZONE OF THE CURRENT UPPER-LEVEL SPLIT FLOW PATTERN.
GFS/NAM/ECM ARE IN EXCELLENT AGREEMENT WITH BROAD UPPER-LEVEL RIDGING BECOMING ESTABLISHED ON MON/TUE. SO TREND TO FAVOR THE WARMER MOS WITH HIGHS AROUND 65 F OVER THE PLAINS.
MODELS ARE IN FAIRLY GOOD AGREEMENT ON THE TIMING AND EVOLUTION OF THE UPPER TROUGH AS IT SWINGS THROUGH OUR AREA TONIGHT. AN UPPER LEVEL TROUGH WILL CROSS THE AREA SUNDAY EVENING.
/ISSUED 605 PM EST SAT JAN 24 2015/ DRY AND CLEAR CONDITIONS ARE PREVAILING ACROSS THE STATE TODAY AS UPPER LEVEL LOW CONTINUES TO LIFT UP THE EAST COAST. WITH INCREASING HIGH LEVEL CLOUDS BY SUNDAY AFTERNOON WITH AS A STRONG AND COLD LOW PRESSURE SYSTEM APPROACHES THE STATE FROM THE NORTHWEST. ATLANTA METRO WILL BE IN THE MID 30S MONDAY MORNING AS WILL MUCH OF NORTH GEORGIA WITH ONLY THE HIGHER ELEVATIONS APPROACHING FREEZING AND ALLOWING FOR MORE SIGNIFICANT ACCUMULATIONS. HAVE UPPED TOTALS IN GRIDS TO INDICATE A HALF AN INCH BUT UP TO AN INCH FOR THE HIGHEST ELEVATIONS.
A strong NW flow aloft persists over the region tonight through Sunday as an upper level ridge, currently along the US west coast, gradually moves back onshore then into the Northern Rockies Sunday night and Monday. The next stronger wave of energy to move over the top of the upper level ridge moves onto BC tonight and northern AB Sunday. As the upper level ridge pushes inland Sunday afternoon any lingering shower activity over the mtns will end with dry conditions thereafter through Monday.
Light westerly winds will begin to veer to the north through the morning as a cold front moves through the region. Northwesterly upper flow will bring a cold front into the area tomorrow, but there will be little if any cold air behind it so expect temperatures to be much like today.
AFTERNOON HIGH TEMPERATURES TODAY TO CLIMB INTO THE LOW TO MID 60S WITH LOWS IN THE MID TO UPPER 30S OVERNIGHT. UPPER-LEVEL RIDGE TO MAINTAIN MAINLY NORTHWEST FLOW ALOFT,,,TRANSITIONING TO ZONAL FLOW BY MIDWEEK.
1107 PM CST SAT JAN 24 2015 LOW PRESSURE OVER THE UPPER MIDWEST WILL DIVE SOUTHEAST THROUGH THE PERIOD AND INTO THE TENNESSEE VALLEY. TRAILING COLD FRONT WILL SWEEP THROUGH THE STATE IN RESPONSE WITH WINDS TURNING MORE TO THE NORTHWEST AND INCREASING SOMEWHAT.
AT THE SURFACE, AN ASSOCIATED LOW PRESSURE SYSTEM WAS ALSO TRACKING SOUTHEAST OVER SOUTHERN IOWA. WINDS IN THE LOWER ATMOSPHERE WILL GRADUALLY WEAKEN DURING THE AFTERNOON HOURS. THE MODELS ARE SHOWING A COOLER DAY FOR SOUTHWEST KANSAS THAN WAS PREVIOUSLY THOUGHT.
GFS/NAM/ECM ARE IN EXCELLENT AGREEMENT WITH BROAD UPPER-LEVEL RIDGING BECOMING ESTABLISHED ON MON/TUE. SO TEND TO FAVOR THE WARMER MOS WITH HIGHS AROUND 65 F OVER THE PLAINS.
TEMPERATURES RANGE FROM THE MID TO UPPER 50S IN UPPER KEYS TO THE MID 60S IN THE LOWER KEYS. A WEAKENING AREA OF HIGH PRESSURE (1021 MB) IS CENTERED OVER THE WESTERN HALF OF THE GULF OF MEXICO WITH A RIDGE AXIS REACHING INTO SOUTH FLORIDA.
1244 AM EST SUN JAN 25 2015 IT WILL BE CLOUDY OVERNIGHT WITH LOW TEMPERATURES RANGING FROM THE MIDDLE 20S OVER MICHIGAN TO THE LOWER 30S OVER CENTRAL INDIANA AND OHIO. HIGH TEMPERATURES SUNDAY WILL BE IN THE LOWER 20S NORTH TO UPPER 30S SOUTH. BRISK NE-N WINDS ON BACKSIDE OF THE LOW SUNDAY EVE MAY CAUSE SOME DRIFTING SNOW. BUT WINDS WILL DIMINISH OVERNIGHT AS LOW PULLS AWAY AND RIDGE APPROACHES ALLOWING TIME TO CLEAR ANY DRIFTED RURAL ROADS BY MONDAY MORNING RUSH. CLOUD COVER SHOULD ALSO DIMINISH OVERNIGHT BUT RIDGE REMAINS TO OUR WEST. NEXT SHRTWV TO TOP WRN RIDGE AND DROP SEWD FROM WRN CANADA THROUGH THE MS/OH VALLEY MON-TUE STILL EXPECTED TO BE QUITE WEAK/SHEARED OUT. LEANED TOWARD COOLER ECMWF MOS TEMPS.
More fog and low clouds are expected once this system moves out of the area overnight and high pressure returns. A ridge of high pressure will rebound late in the week. /Pelatti 06Z TAFS: The area stratus and fog remain problematic in the aviation forecasts for the next 24 hours with the ridge of high pressure in place and abundant low level moisture lingering.
ESPECIALLY ACROSS NEW YORK STATE ALONG A SOUTHWARD DROPPING COLD FRONT. ISSUED A SHORT TERM, UNTIL MIDNIGHT, WINTER WEATHER ADVISORY FOR CENTRAL NY/NRN TIER OF PA FOR AREAS OF FREEZING DRIZZLE. WE ANTICIPATE THE ACTIVITY TO CONTINUE UNTIL THEN WHEN CAA WILL COOL THE COLUMN ENOUGH FOR ANY REMAINING FREEZING PRECIP TO CHANGE TO FROZEN. INVERTED TROF EXPECTED TO BRING LGT SNOW TO MOST OF THE AREA ON MONDAY AS CYCLOGENESIS OCCURS OFF THE ERN SEABOARD.
UPPER LEVEL RIDGE WILL BUILD ACROSS THE AREA WHILE AN UPPER LOW REMAINS ALMOST STATIONARY OVER THE BAJA CA COAST. THIS LOW PRESSURE SYSTEM WILL STREAM FEW TO SCT HIGH CLOUDS THROUGH THE SHORT TERM PERIOD. ABUNDANCE OF SUNSHINE TODAY WILL ALLOW FOR TEMPERATURES TO REACH THE LOWER 70S ACROSS THE CWA. REINFORCING HIGH PRESSURE MOVES SOUTH RETURNING WINDS MORE NORTHERLY AND THICKNESS VALUES GRADUALLY LOWER A BIT MORE. LOW TEMPS EARLY MONDAY MORNING WILL BE IN THE LOW TO MID 40S AND HIGH TEMPERATURES WILL BE IN THE LOW 70S.
WATER VAPOR IMAGERY/NAM AND GFS STREAMLINE OUTPUT DEPICT/SUGGEST AN UPPER TROUGH WITH AXIS OVER THE PLAINS.
PLEASANT WEATHER EXPECTED TODAY WITH CHILLY MORNING TEMPS WARMING INTO THE LOW 60S ACROSS MUCH OF THE AREA THIS AFTERNOON UNDER CLEAR SKIES. HIGH PRESSURE SITUATED OVER THE GOMEX AND FL PENINSULA WILL MOVE OFF TO THE SOUTH TODAY AS SFC BOUNDARY PROGRESSES TOWARDS THE AREA ALLOWING WINDS TO SHIFT FROM NORTHWEST TO SOUTHWEST THIS AFTERNOON AT 5 TO 10 MPH. WITH INCREASED CLOUDS AND SW FLOW LOW TEMPERATURES WILL COME UP TO NEAR NORMAL IN THE LOW TO MID 40S ACROSS SE GA AND MID TO UPPER 40S FOR MUCH OF NE FL.
COMBINED WITH THE APPROACH OF S/W TROF LATE. SHALLOWING MOISTURE IN OUR SW COUNTIES LATE IN THE DAY MAY RESULT IN A CHANCE OF FREEZING DRIZZLE.
WINDS VEER TO NORTH/NNW AND INCREASE BRIEFLY SUNDAY AFTN BEHIND A COLD FRONT BEFORE DIMINISHING EARLY SUNDAY EVENING. MOSTLY LIGHT WEST WINDS TONIGHT TO BECOME NW/NORTH AND INCREASE SOME BY NOON SUNDAY WITH THE PASSAGE OF A COLD FRONT. THE AFOREMENTIONED DISTURBANCE MAKING HEADWAY INTO THE MIDWEST WILL VEER WINDS MORE NORTH/NORTHWESTERLY DURING THE MORNING INTO THE AFTERNOON AS SOMEWHAT COOLER AIR ALOFT ATTEMPTS TO BACKDOOR INTO THE FAR SOUTHEAST PANHANDLE AND ROLLING PLAINS.
MANY SPOTS WILL SEE READINGS DROP TO NEAR OR JUST BELOW FREEZING. TEMPERATURES MAY BOTTOM OUT AROUND 06Z-09Z AND SLOWLY RISE TOWARD DAYBREAK AS WINDS INCREASE AHEAD OF AN APPROACHING UPPER-TROUGH.
Despite the cold front passage on Sunday, temperatures Monday will rebound back into the 50s across the western half of the forecast area as heights begin to rise aloft courtesy of a building ridge across the Rockies.
Freezing level heights are very low, so any activity that is convective in nature, could result in a lightning strike or two, and maybe a little hail.
350 AM CST SUN JAN 25 2015 TODAY WILL BE THE FINAL DAY OF NORTHWEST FLOW BEFORE DEEP RIDGING ALOFT TAKES HOLD.
TODAY THROUGH TONIGHT THE SHORT TERM PERIOD WILL BE DOMINATED BY THE INFLUENCE OF HIGH PRESSURE CURRENTLY CENTERED BENEATH AN AREA OF CONFLUENT FLOW ALOFT AND CENTERED OVER FAR NORTHWEST ONTARIO. NORTHEAST WINDS AROUND THE PERIPHERY OF THIS HIGH HAVE BEGUN TO FILL INTO SOUTHEAST MICHIGAN BEHIND THE COLD FRONT THAT IS MAKING ITS WAY THROUGH THE CWA. LOW-LEVEL DRY ADVECTION WILL INCREASE MARKEDLY THIS AFTERNOON INTO THIS EVENING AS HIGH PRESSURE BUILDS INTO ONTARIO.
A MORE SIGNIFICANT COLD FRONT IS PROGGED BY NEXT SAT.
1240 AM EST SUN JAN 25 2015 CROSSING LOW PRESSURE WILL BRING WIDESPREAD SNOW SUNDAY THROUGH MONDAY. A TROUGH OF LOW PRESSURE DIVING SOUTH ACROSS THE MIDWESTERN STATES ON SUNDAY WITH THE MID LEVEL LOW CENTER PROGGED TO BE OVER KENTUCKY BY SUNDAY EVENING BEFORE SHIFTING TO THE EAST THEN UP THE COAST AS A STRONG COASTAL LOW DEVELOPS OFF THE CAROLINA COAST.
NON CONVECTIVE LOW LEVEL WIND SHEAR IS POSSIBLE WITH THE PASSAGE OF THIS TROUGH THROUGH 15Z. AS STRONG A STRONG SURFACE CYCLONE DEVELOPS OVER THE MID- MISSISSIPPI VALLEY TOMORROW.
WAA TODAY WITH A FEW MODELS GENERATING LIGHT QPF ALONG THE WARM FRONT SO WILL KEEP A SLIGHT CHANCE FOR LIGHT RAIN AND HIGH SKY COVER AS THE FRONT PUSHES EASTWARD DURING THE AFTERNOON INTO THE EARLY EVENING.
BUT ALLOW FOR A WEAK COLD FRONT TO MOVE THROUGH THE AREA SUNDAY MORNING THROUGH EARLY AFTERNOON.
A COLD FRONT THAT HAS ALMOST MOVED COMPLETELY THROUGH THE CWA BROUGHT A MIX OF RAIN AND DRIZZLE/FREEZING DRIZZLE ALONG WITH FALLING TEMPERATURES TODAY. MAINLY OVER THE HIGHER TERRAIN OF NCENTRAL UPPER MI AND AT THE TIP OF THE KEWEENAW. SUNDAY WILL NOT SEE MUCH WARMING AS HIGH TEMPERATURES WILL BE IN THE LOW TO MID TEENS. NAM SHOWS A CLOSED 500 MB LOW OVER SOUTHERN IL 00Z MON WITH A BROAD RIDGE OVER THE WESTERN U. THE RIDGE MOVES INTO THE PLAINS BY 00Z WED WHILE A DEEP 500 MB TROUGH MOVES INTO THE EASTERN U. GFS AND ECMWF SHOW A 500 MB TROUGH OVER THE EAST COAST 12Z WED WITH COLD AIR POISED JUST TO THE NORTH OF THE AREA. THE COLD AIR REALLY MOVES IN ON FRI WITH A DEEP 500 MB TROUGH THAT DIGS INTO THE EASTERN U.
It now appears there is decent agreement that the low will track se much farther sw through the Evansville Tri State region Sunday. Enough cold air may work in on the back side of the low Sunday evening to turn any leftover precip to light snow or flurries, but not expecting any travel impacts at this time. High pressure will make a short visit on Monday, before another cold front sweeps through and brings colder conditions in for Tue.
216 AM EST SUN JAN 25 2015 LOW PRESSURE MOVES FARTHER AWAY TONIGHT.
MANY SPOTS WILL SEE READINGS DROP TO NEAR OR JUST BELOW FREEZING. TEMPERATURES MAY BOTTOM OUT AROUND 06Z-09Z AND SLOWLY RISE TOWARD DAYBREAK AS WINDS INCREASE AHEAD OF AN APPROACHING UPPER-TROUGH. AN UPPER LEVEL TROUGH WILL CROSS THE AREA SUNDAY EVENING.
SHOULD SEE A BREAK FROM THE ALMOST DAILY SHORT WAVE PASSAGES WE HAVE BEEN SEEING AS UPPER RIDGE SHIFTS EAST. LONG WAVE TROUGH WAS OVER EASTERN NORTH AMERICA WHILE A LONG WAVE RIDGE WAS OVER WESTERN CANADA. WESTERN CANADA RIDGE WEAKENS SLIGHTLY OVER THE PERIOD. EASTERN TROUGH AMPLIFIES A BIT. SHORT WAVE TROUGHS WILL CONTINUE TO MOVE THROUGH THE FLOW IN THIS PROGRESSIVE PATTERN.
AS THE UPPER LOW/COLD FRONT APPROACHES THE LOWER OHIO VALLEY REGION TODAY. WITH TEMPS ACROSS THE FORECAST AREA PROGGED TO MAKE IT INTO THE LOW TO MID 50S. THE UPPER TROUGH SHOULD REMAIN ACROSS THE EASTERN PORTION OF THE U.
339 AM CST SUN JAN 25 2015 LOW PRESSURE CENTERED DIRECTLY OVER KNOXVILLE WILL CONTINUE TO PUSH SOUTHEAST THIS MORNING BEFORE CENTERING ITSELF OVER SOUTHERN ILLINOIS BY AROUND MIDDAY TODAY. THE HIGHER SNOW AMOUNTS LOOK TO BE TOWARDS THE ALO TO MIW AREA WHERE THE RAIN LOOKS TO SHIFT TO SNOW QUICKEST AND REMAIN IN THE BETTER FORCING AND DEEP MOISTURE FOR MUCH OF THE MORNING. PERSISTENT RIDGE ALOFT AT H500 BUILDING SLIGHTLY EAST THROUGH MONDAY MORNING WITH NEXT UPSTREAM WAVE EXPECTED TO PASS EAST OF THE AREA ON MONDAY. AS A TROUGH PASSES EAST ON MONDAY MIXING WILL HELP BUMP TEMPS INTO THE 40S AND LOWER 50S OVER THE AREA.
WAA TODAY WITH A FEW MODELS GENERATING LIGHT QPF ALONG THE WARM FRONT. RELATIVELY WARMER BOUNDARY LAYER AIR IS GENERATING A NARROW PATCH OF FREEZING RAIN PRIMARILY OVER JAMESTOWN. THE PRECIP TYPE SHOULD CONTINUE TO TRANSITION FROM RAIN/FREEZING RAIN TO ALL SNOW OVER THE JAMES RIVER VALLEY BY THIS EVENING. LOW PRESSURE MOVING ACROSS SASKATCHEWAN WILL GENERATE DRY AND WARM SOUTHWESTERLY FLOW OVER WESTERN AND CENTRAL NORTH DAKOTA SUNDAY.
IT WILL TAKE SOME TIME TO SATURATE THE LOW LEVELS ONCE THE PRECIP SHIELD IS OVERHEAD. MODEL SOUNDINGS DO INDICATE THAT THERE SHOULD BE RAPID COOLING TO BELOW FREEZING IN THE LOW LEVELS ABOVE THE SURFACE THANKS TO EVAPORATIVE COOLING. TEMPS TOMORROW WILL BE SLIGHTLY COOLER. THE LOSS OF ICE ALOFT MONDAY MORNING RESULTS IN SOME LIGHT FREEZING DRIZZLE BEING CARRIED INTO THE AFTERNOON ACROSS OUR WEST CENTRAL WISCONSIN COUNTIES.
/ISSUED 914 PM CST SAT JAN 24 2015/ A COLD FRONT WILL SWEEP ACROSS THE AREA LATE TONIGHT AND EARLY SUNDAY AS AN UPPER LEVEL DISTURBANCE PASSES BY TO OUR NORTHEAST.
IN THE WAKE OF THE TROUGH. IN THE WAKE OF THE TROUGH. FOR THE LOW TONIGHT THOUGH.
EXPECT MIN TEMPERATURES TO COOL TO THE LOWER 30S. A STRONG EASTERN UNITED STATES TROUGH OR A SOUTHWEST CUTOFF LOW. FORECAST LEANED TOWARDS THE EASTERN UNITED STATES TROUGH WINNING AS SHOWN BY THE EUROPEAN MODEL.
253 AM EST SUN JAN 25 2015 COLD/STRONG CANADIAN HIGH PRESSURE REMAINS CENTERED NORTH OF MINNESOTA EARLY THIS MORNING. WHILE LOW PRESSURE CHURNS ITS WAY THRU THE UPPER MISSISSIPPI VALLEY. MUCH OF MICHIGAN REMAINS UNDER THE STRENGTHEN RIDGE AXIS ASSOCIATED WITH HIGH PRESSURE TO OUR NW. STRONG HIGH PRESSURE. STRONG COLD HIGH PRESSURE WILL MOVE OVERHEAD TONIGHT.
235 AM EST SUN JAN 25 2015 CROSSING LOW PRESSURE WILL BRING WIDESPREAD SNOW SUNDAY THROUGH MONDAY. A TROUGH OF LOW PRESSURE DIVING SOUTH ACROSS THE MIDWESTERN STATES ON SUNDAY WITH THE MID LEVEL LOW CENTER PROGGED TO BE OVER KENTUCKY BY SUNDAY EVENING BEFORE SHIFTING TO THE EAST THEN UP THE COAST AS A STRONG COASTAL LOW DEVELOPS OFF THE CAROLINA COAST.
AND ASSOCIATED COLD FRONT ACROSS THE REGION DURING THE LATE AFTERNOON AND EARLY EVENING HOURS. WITH THE SUBSTANTIAL DRY LAYER IN THE LOWER LEVELS. CONDITIONS LOOK DRY FOR MONDAY WITH ANY LINGERING CLOUDS CLEARING THROUGH THE MORNING AS THE UPPER TROUGH SHIFTS EAST OF THE AREA AND SURFACE RIDGING BEGINS TO BUILD IN.
BY TONIGHT LOW PRESSURE WILL PASS BY FAR TO THE NORTH BUT THIS WILL AGAIN TURN THE WINDS TO A NICE MIXY WESTERLY DIRECTION. BY SUNRISE MONDAY MORNING TEMPERATURES SHOULD BE FROM ABOUT 35 TO 40 IN MANY LOCATIONS WITH SOME COOLER READINGS IN NORTHWEST IOWA WHERE WINDS WILL BE SLOWER TO DEVELOP. STAYING ON THE HIGH SIDE OF GUIDANCE.