Aikyam-Lab/Synoptic-Bench huggingface dataset:
552 AM CDT FRI JUN 5 2015 EARLY MORNING WATER VAPOR IMAGERY TOGETHER WITH GFS 500MB HEIGHTS AND WINDS SHOWS A LONGWAVE TROUGH OFF THE CALIFORNIA COAST. WITH WEAK RIDGING OVER THE CENTRAL CONUS. AND A BROADER TROUGH OFF THE EASTERN COAST. THE HIRES MODELS SUCH AS THE ROOF- ARW/NMM/HOP AND HRRR ALL INDICATE SHOWERS AND PERHAPS EVEN AN ISOLATED THUNDERSTORM DEVELOP ALONG THE BUFFALO RIDGE AROUND 11Z.
140 AM EDT FRI JUN 5 2015 A MID/UPPER LEVEL LOW DRIFTS OFF THE NORTH CAROLINA COAST FRIDAY. A WEAK COLD FRONT SINKS SOUTH OVERNIGHT FRIDAY NIGHT INTO SATURDAY MORNING.
TODAY THROUGH SATURDAY NIGHT SOUTHWEST FLOW ALOFT CONTINUES ACROSS THE ROCKIES TO NRN PLAINS AS A PERSISTENT UPPER LOW DRIFTS ACROSS SRN CALIFORNIA. CHANCES OF STORMS WILL BE ON THE DECLINE AS COOLER MORE STABLE AIR CONTINUES TO PUSH INTO THE AREA SAT NIGHT.
WITH DRY HIGH PRESSURE TO THE NORTHEAST KEEPING IT FROM SUSTAINING ITSELF THE FURTHER EAST IT MOVES. MODELS ARE IN PRETTY GOOD AGREEMENT THAT AS THE HIGH PUSHES SOUTHWARD. WILL THEN SEE A STRONGER LOW PRESSURE SYSTEM APPROACH THE AREA.
HIGH PRESSURE AT THE SURFACE AND RIDGING ALOFT WILL OVERALL KEEP THE WEATHER QUIET ACROSS THE FORECAST AREA THROUGH THE PERIOD. A DISTURBANCE EMBEDDED IN NORTHWEST FLOW ALOFT COULD BRING SOME LOW-END RAIN CHANCES TO LOCALES PRIMARILY ALONG AND NORTH OF THE HIGHWAY 82 CORRIDOR ON SATURDAY.
COOLER IN THE EAST WITH THE CONTINUED ONSHORE FLOW OFF THE LAKE.
AS A MID LEVEL TROUGH CONTINUES TO HOLD OVER FLORIDA TODAY. A SURFACE BASED INVERTED TROUGH CENTERED OVER THE WESTERN CARIBBEAN CAN BE SEEN ON INFRARED SATELLITE IMAGERY. THE NORTHERN PORTION OF THIS INVERTED TROUGH WILL DETACH AND MOVE NORTHEAST OF FLORIDA TONIGHT AND SATURDAY AS THE MID LEVEL TROUGH PUSHES INTO THE ATLANTIC.
314 AM CDT WED APR 22 2015 07Z/2AM SURFACE ANALYSIS SHOWS A COLD FRONT SETTLING SOUTHWARD TOWARD THE OHIO RIVER, WHILE A POST-FRONTAL BAND OF LIGHT SHOWERS PERSISTS ACROSS CENTRAL ILLINOIS. WINDS WILL QUICKLY DIMINISH AFTER SUNSET TONIGHT AS THE ATMOSPHERE DECOUPLES: HOWEVER, WITH RIDGE AXIS REMAINING WEST OF THE MISSISSIPPI RIVER, THINK A LIGHT WESTERLY BREEZE OF AROUND 5MPH WILL PERSIST THROUGH THE OVERNIGHT HOURS. THIS MAY INHIBIT WIDESPREAD FROST FORMATION DESPITE LOW TEMPERATURES DROPPING INTO THE LOWER TO MIDDLE 30S. HIGH PRESSURE WILL DRIFT OVERHEAD ON THURSDAY, PROVIDING A SUNNY AND COOL DAY WITH HIGHS AROUND 60. ANOTHER COLD AND POTENTIALLY FROSTY NIGHT IS SETTING UP FOR THURSDAY NIGHT, AS RIDGE AXIS SLOWLY SHIFTS EASTWARD INTO INDIANA BY 12Z FRI. UPPER LOW CURRENTLY SPINNING OVER SOUTHERN CALIFORNIA WILL GET EJECTED NORTHEASTWARD BY A NORTHERN STREAM WAVE COMING INTO THE PACIFIC NORTHWEST.
428 AM CDT WED APR 22 2015 A LOW AMPLITUDE UPPER LEVEL RIDGE OVER THE SOUTHERN HIGH PLAINS REGION WILL TAKE A BEATING TODAY AS ENERGY CONTINUES TO RIDE A MODEST SUBTROPICAL JET FROM THE DESERT AREAS INTO OUR REGION. IN SPITE OF THE RIDGE AND A MODEST CAP IN MID LEVELS. THIS WOULD RESULT IN COOLER SURFACE TEMPERATURES AND INHIBIT CHANCES FOR CONVECTIVE INITIATION AS UPPER RIDGING CONTINUES TO STREAM IN WARMER AIR ALOFT FROM THE SOUTHWEST. PERHAPS A LITTLE BETTER CHANCE FOR THUNDERSTORM ACTIVITY MAY COME THURSDAY EVENING/NIGHT WITH THE TRANSITION TO CYCLONIC FLOW AHEAD OF THE SOUTHWESTERN CONUS TROUGH. STOUT H85 THERMAL RIDGING AND VEERING SURFACE WIND FIELDS. CORRESPONDING TO LEE TROUGHING CENTERED IN SOUTHEAST COLORADO.
LATEST WATER VAPOR IMAGERY SHOWS AN UPPER LOW OVER SOUTHERN CALIFORNIA AND A WEAK SHORT WAVE OVER NORTHEAST MEXICO. HIGH PRESSURE REMAINS CENTERED OVER THE NORTHEAST GULF OF MEXICO THIS MORNING. DRIER AIR WORKS DOWN INTO THE LOWER LAYERS LATER TODAY AND ALLOWS SOME MILD CAPPING TO DEVELOP. HIGH TEMPERATURES TODAY WILL RANGE FROM THE LOWER 80S NEAR THE COAST TO THE MID AND UPPER 80S ELSEWHERE. LOW TEMPERATURES TONIGHT WILL BE IN THE LOW TO MID 70S.
THIS ACTIVITY IS OCCURRING AHEAD OF A COLD FRONT CURRENTLY STRETCHING FROM FARMINGTON MO TO BLOOMINGTON IN.
407 AM CDT WED APR 22 2015 UPPER LOW PARKED OVER THE NORTHERN GREAT LAKES EARLY THIS MORNING PLACES OUR REGION IN PERSISTENT NORTHWEST FLOW THROUGH THE SHORT TERM PERIOD. SIGNIFICANT DRYING CONTINUES TO PUSH IN FROM THE NORTHWEST AS CANADIAN HIGH PRESSURE AXIS ADVANCES SOUTH. EXTENT OF WRAP AROUND MOISTURE FROM THE LOW WILL MAKE LITTLE PROGRESS TO THE EAST TODAY AS THE BACK EDGE OF THE CLOUD LINE /CURRENTLY ACROSS EASTERN MN/ MOVES SLIGHTLY TO THE EAST. THE PERIOD BEGINS QUITE PLEASANT WITH SURFACE RIDGING STRETCHING SOUTHEAST ACROSS THE UPPER MISSISSIPPI VALLEY.
A COLD FRONT HAS ALSO BECOME NEARLY STATIONARY OVER THE LAKE OKEECHOBEE REGION THIS AFTERNOON. WEAK LOW PRESSURE SHOULD DEVELOP OVER THE GULF COAST STATES WEDNESDAY NIGHT AND MOVE EASTWARD THROUGH THE SOUTHEAST UNITED STATES ON THURSDAY. THIS WILL ALLOW FOR THE STATIONARY FRONT TO MOVE NORTHWARD AS A WARM FRONT WEDNESDAY NIGHT INTO THURSDAY INTO NORTHERN FLORIDA KEEPING THE TROPICAL AIR MASS IN PLACE OVER SOUTH FLORIDA.
501 AM EDT WED APR 22 2015 HIGH PRESSURE WILL MOVE TO THE EAST THIS MORNING. LOW PRESSURE WILL THEN CROSS THE REGION TONIGHT THROUGH THURSDAY.
IT APPEARS ON THURSDAY THAT THE STRONGEST WINDS WILL LIKELY NOT COINCIDE WITH THE LOCATION OF THE LOWEST RH VALUES.
ANY FOG SHOULD DISSIPATE AFTER SUNRISE BUT CIGS WILL BE SLOW TO LIFT BUT VFR CONDITIONS ARE GENERALLY EXPECTED TO PREVAIL BY 22/18Z BUT THE LOW CLOUDS MAY LINGER A BIT LONGER AT KLFK. CONVECTION IS EXPECTED TO DEVELOP ALONG A COLD FRONT WEDNESDAY AFTERNOON. /ISSUED 919 PM CDT TUE APR 21 2015/ SHOWERS SHIFTING EAST THIS EVENING ALONG A WEAK DISTURBANCE IN THE LOW TO MID-LEVEL ZONAL FLOW. CONDITIONS TO IMPROVE FROM MOSTLY CLOUDY TO PARTLY CLOUDY OVERNIGHT AS WEAK RIDGING SETS IN.
123 AM EDT WED APR 22 2015 HIGH PRESSURE WILL BUILD OVER THE AREA THROUGH WEDNESDAY MORNING. A WEAK COLD FRONT WILL MOVE THROUGH THE AREA EARLY THURSDAY WITH LIMITED MOISTURE. HIGH PRESSURE WILL BE CENTERED JUST SOUTH OF THE FORECAST AREA TONIGHT. THEN COOL DOWN SLIGHTLY DUE TO THE COLD FRONT THURSDAY.
THIS AFTERNOON A WEAK COLD FRONT WILL MOVE ACROSS THE TENNESSEE VALLEY.
335 AM EDT WED APR 22 2015 SHORT TERM BEGINS WITH HIGH PRESSURE REMAINING IN CONTROL OF THE LOCAL WEATHER WITH ITS CENTER ALONG THE GULF COAST AND LIGHT SOUTHWEST RETURN FLOW JUST OFF THE SURFACE.
COOLER WEATHER PATTERN WILL REMAIN IN PLACE AS CENTRAL INDIANA REMAINS UNDER THE INFLUENCE OF A BROAD LOW PRESSURE SYSTEM OVER EASTERN ONTARIO.
328 AM CDT Wed Apr 22 2015 Northwest flow continues to dominate the Central Plains with upper low still over the Great Lakes and cutoff low south of ridge in the western states. A stronger wave was rotating around the southern edge of the low and brought a cold front through all but southeastern corner of Kansas as of 08Z.
243 AM EDT WED APR 22 2015 UPPER LEVEL LOW PRESSURE OVER THE GREAT LAKES WILL MAINTAIN COOL AND UNSETTLED WEATHER THROUGH THE WEEK.
THE LARGE OCCLUDED LOW PRESSURE AREA OVER THE GREAT LAKES AND ONTARIO CANADA WILL MOVE LITTLE TODAY.
THE STRONG UPPER LOW WILL CONTINUE TO KEEP THE ARROWHEAD UNDER SOME CYCLONIC FLOW. LINGERING LOW CLOUDS/SNOW SHOWERS OVER THE ARROWHEAD AND NRN WISCONSIN AREAS WILL EXIT TO THE EAST WED NIGHT/THURS AS A RIDGE OF HIGH PRESSURE AND DRIER AIR BUILDS INTO WESTERN MN. ALTHOUGH THERE REMAINS SOME MODEL DISAGREEMENT IN THE EASTWARD EXTEND OF THE RIDGE AXIS/DRIEST AIR OVER MN THURSDAY AFTERNOON. THE COMBINATION OF SFC RIDGING AND THE VERY DRY AIR IN PLACE WITH DEW POINTS IN THE LOW TEENS TO SINGLE DIGITS. THE LOWEST RH VALUES AROUND 20% WILL BE OVER CENTRAL MINNESOTA/BRAINERD LAKES REGION. WITH THE HIGHER GUSTS OF 15 TO 20 KT EXPECTED TO BE CONFINED TO LOCATIONS IN THE MN ARROWHEAD AND OVER NRN WISCONSIN.
UPPER LEVEL RIDGING WILL CONTINUE TO BUILD TODAY. WHERE WARMER TEMPERATURES AND BETTER MOISTURE WILL REMAIN AHEAD OF THE FRONT. A RENEWED AREA OF LEE TROUGHING SETS UP AND PUSHES THE CONVECTIVE CHANCES EASTWARD AS THE FRONTAL BOUNDARY SINKS SOUTH AND AXIS OF CONVERGENCE SHIFTS INTO THE CENTRAL AND EASTERN PANHANDLES.
COOL HIGH PRESSURE WILL DOMINATE THE CENTRAL PLAINS TODAY BEHIND A COLD FRONT. AS HIGH PRESSURE RIDGING MOVES INTO THE MISSOURI VALLEY LATER TODAY AND TONIGHT, NORTHEAST WINDS OF 15 TO 25 MPH EARLY, BECOME LIGHT EASTERLY AROUND 10-12 MPH THIS AFTERNOON, THEN SOUTHEASTERLY UPSLOPE THIS EVENING.
347 AM CDT WED APR 22 2015 THE STRONG UPPER LOW THAT HAS BEEN PERSISTENT OVER THE AREA FOR A COUPLE DAYS NOW IS MAINTAINING MOIST CYCLONIC FLOW OVER THE REGION. TODAY THIS PATTERN WILL CONTINUE ACROSS THE AREA WITH THE CONTINUING SNOW SHOWERS BECOMING MIXED WITH RAIN DURING THE AFTERNOON FOR AWHILE AS TEMPERATURES GET ABOVE FREEZING. THIS UPPER LOW MAKES BETTER PROGRESS AT PULLING EAST TONIGHT. HIGH PRESSURE WILL REMAIN IN CONTROL FOR AT LEAST THE FIRST PART OF THURSDAY NIGHT.
WHICH WILL BE LIFTING NORTHWARD SLOWLY OVER THE NEXT COUPLE DAYS AHEAD OF AN UPPER LOW OVER SRN CALIFORNIA WHICH WILL MOVE LITTLE THROUGH THURSDAY. UPPER RIDGE AXIS WILL BE OVER THE REGION BUT IMPULSES WILL MOVE THROUGH THE RIDGE AND ACROSS THE CWA HELPING TO SET OFF PCPN MAINLY IN THE AFTERNOONS AND EVENINGS.
1124 PM MDT TUE APR 21 2015 A CLOSED LOW AT H7 OVER SOCAL WILL SPIN SOME ENERGY TOWARD THE 4 CORNERS TONIGHT. BUT A FEW SHOWERS MAY PERSIST OVER THE HIGHER TERRAIN OF SOUTHEAST UTAH THROUGH THE NIGHT. SHORT WAVE ROTATING NORTHWARD AHEAD OF SRN CALIF CLOSED LOW CIRCULATION GETS STRETCHED. WITH THE HIGHEST CHANCE OVER THE SAN JUAN MOUNTAINS.
155 AM EDT WED APR 22 2015 A COLD FRONT WILL APPROACH FROM THE MIDWEST TONIGHT.
WILL CONTINUE TO MONITOR FOR THE POSSIBILITY OF SOME HAIL AND GUSTY WINDS GIVEN THE STEEP LAPSE RATES AND LOW FREEZING LEVELS. WILL KEEP IT DRY WEDNESDAY NIGHT THROUGH THURSDAY WITH WEAK HIGH PRESSURE ANGLING IN FROM THE UPPER MIDWEST.
348 AM CDT WED APR 22 2015 HIGH PRESSURE CONTINUES TO SAG SOUTH THIS MORNING. MIN RH VALUES WILL ALSO BE DROPPING INTO THE LOW 20S. HIGH PRESSURE WILL BE THE DOMINATE FEATURE TONIGHT INTO THURSDAY MORNING. SO AGAIN TRENDING TOWARD THE COOLER GUIDANCE FOR LOW TEMPERATURES.
327 AM EDT WED APR 22 2015 HIGH PRESSURE WILL SHIFT OFF THE COAST BY THIS EVENING AND A WEAK COLD FRONT WILL MOVE THROUGH THE AREA EARLY THURSDAY WITH LIMITED MOISTURE.
328 AM EDT WED APR 22 2015 A BROAD AREA OF LOW PRESSURE WILL CONTINUE TO DOMINATE THE WEATHER OVER THE GREAT LAKES THROUGH THE END OF THE WEEK. UPPER LOW REMAINS IN PLACE ACROSS THE ONTARIO/QUEBEC REGION. AT THE SURFACE A COLD FRONT CONTINUES TO MOVE THROUGH THE AREA SPREADING RAIN SHOWERS INVOF THE FRONT. THE NAM SHOWS NO BIG CHANGES IN STORE FOR NRN OHIO AND NWRN PA THROUGH THURSDAY AT LEAST WITH PLENTY OF MOISTURE ROTATING ACROSS THE AREA AROUND THE CLOSED STAGNANT UPPER LOW.
218 AM EDT WED APR 22 2015 A COLD FRONT WILL MOVE THROUGH LATE TONIGHT INTO WEDNESDAY MORNING BRINGING SHOWERS TO THE AREA.
156 AM EDT WED APR 22 2015 A LARGE UPPER LEVEL LOW PRESSURE SYSTEM ACROSS THE GREAT LAKES AND ONTARIO WILL DRIFT SLOWLY EASTWARD THROUGH THE END OF THE WEEK. SOME SNOW SHOWERS IN THE HIGHER ELEVATIONS. BUT LOCALLY BELOW FREEZING IN THE NRN ADIRONDACKS AND ACROSS FAR NERN VT.
447 AM EDT WED APR 22 2015 A COLD FRONT WILL BRING WIDESPREAD SHOWERS TO OUR REGION TODAY. QUIET FOR NOW BUT A SFC COLD FRONT IN ERN OHIO WILL MOVE EAST THROUGH NY AND PA TODAY. ONCE THERE THURSDAY THE LOW STALLS. FORCING BECOMES WEAK ON THE BACK SIDE OF THE LOW. REGARDING TO WHAT DEGREE OUR REGION EXPERIENCES PERIPHERAL INFLUENCES FROM THAT UPPER LOW. WITH 850MB TEMPERATURES A WAYS BELOW FREEZING.
245 AM MST WED APR 22 2015 A CHANGE IN THE WEATHER PATTERN WILL TAKE PLACE OVER THE NEXT COUPLE DAYS AS A LARGE LOW PRESSURE SYSTEM MOVES INTO THE REGION.
636 AM EDT WED APR 22 2015 A BROAD AREA OF LOW PRESSURE WILL CONTINUE TO DOMINATE THE WEATHER OVER THE GREAT LAKES THROUGH THE END OF THE WEEK. UPPER LOW REMAINS IN PLACE ACROSS THE ONTARIO/QUEBEC REGION. AT THE SURFACE A COLD FRONT CONTINUES TO MOVE THROUGH THE AREA SPREADING RAIN SHOWERS INVOF THE FRONT. THE NAM SHOWS NO BIG CHANGES IN STORE FOR NRN OHIO AND NWRN PA THROUGH THURSDAY AT LEAST WITH PLENTY OF MOISTURE ROTATING ACROSS THE AREA AROUND THE CLOSED STAGNANT UPPER LOW.
NOT AS WARM TODAY AS A COLD FRONT OVER SE OREGON THESE WEE EARLY MORNING HOURS. COOLER THURSDAY IN POST-FRONTAL DRY WEATHER.
402 AM CDT WED APR 22 2015 ELONGATED HIGH PRESSURE FROM CANADA TO THE MISSOURI BASIN DRIFTS EAST TODAY SETTING UP A COOL SOUTHERLY RETURN FLOW FROM KANSAS. THE RAP MODEL INDICATES A WARM FRONT WILL DEVELOP ACROSS WRN NEB WHICH MOVES EAST THIS AFTERNOON AND TONIGHT. THE OBVIOUS CULPRIT IS 700MB FRONTOGENESIS AND THE DEVELOPING WARM FRONT. LOWS TONIGHT FALL INTO THE 30S TO NEAR FREEZING EAST OF HIGHWAY 83. LONG WAVE TROUGH WILL BE MOVING ONSHORE THE WEST COAST THURSDAY. WITH FLOW ALOFT BECOMING SOUTHWEST AHEAD OF THE TROUGH ACROSS THE CENTRAL PLAINS.
OR WEAK COLD FRONTAL PASSAGE WILL HELP SPARK ISOLATED TO WIDELY SCATTERED EVENING SHOWERS. WELL PRONOUNCED 850/700 MB THETA-E RIDGE AXIS DEVELOPS NORTH TO SOUTH IN THE AFTERNOON ALONG THE LARAMIE VALLEY WITH A NICE CONVERGENCE AXIS SETTING UP CENTERED OVER THE LARAMIE VALLEY. AREAL COVERAGE WILL BE MINIMIZED BY RIDGING ALOFT.
EXCEPT FOR A LITTLE SLIVER EAST OF THE BUFFALO RIDGE WHERE NORTHWEST WINDS WILL STILL HOLD UP A LITTLE. LOWS WILL VARY FROM THE 20S NORTH AND EAST TO THE LOWER 30S CLOSE TO THE MISSOURI RIVER VALLEY.
FLOW ALOFT TRANSITIONS FROM NORTHWEST TO MORE ZONAL THURSDAY AS A ROCKY MOUNTAIN UPPER LEVEL RIDGE BREAKS DOWN.
139 AM EDT WED APR 22 2015 A COLD FRONT WILL SWEEP ACROSS THE AREA WEDNESDAY.
AS A COLD FRONT WILL SAG INTO AR. THE COLD FRONT WILL SWING WINDS TO THE NW TO NE ON WEDNESDAY AND BE 5 TO 15 MPH.
400 AM CDT WED APR 22 2015 ALOFT: THE FLOW REMAINS SPLIT FLOW OVER N AMERICA WITH A TROF OVER THE E AND A SEMI-PROGRESSIVE RIDGE OVER THE W. A CUT-OFF LOW WAS UNDERNEATH OVER SRN CA WITH CONFLUENT FLOW OVER THE SE USA. THE AXIS OF THIS HIGH WILL GRADUALLY DRIFT E OF THE REGION THRU TONIGHT.
A COLD FRONT WILL DROP SOUTH ACROSS THE GREAT VALLEY LATER TODAY THROUGH EARLY THIS EVENING PRODUCING A COUPLE SHOWERS AND POSSIBLY AN ISOLATED THUNDERSTORM.
A COLD FRONT WILL BRING WIDESPREAD SHOWERS TO OUR WHOLE REGION WEDNESDAY. SCATTERED MAINLY LIGHT SHOWERS WERE OVER THE WRN/NRN CWA BUT VERY DRY AIR IN THE LOW LEVELS IS KEEPING ANY RESULTING RAINFALL LIGHT. A SFC TROF WILL DROP THROUGH THE AREA AT THE SAME TIME A WEAK SFC WAVE LIFTS FROM CENTRAL PA TO SRN NEW ENGLAND.
347 AM CDT Wed Apr 22 2015 For today, cooler temperatures are expected in the wake of a cold front which passed through the region late last evening.
COLD AIR ADVECTION WILL RESULT COOLER TEMPERATURES TODAY. BUT COMBO OF INCREASING LOW LEVEL FLOW/MOISTURE AND WARM FRONT SHOULD RESULT IN INCREASING COVERAGE THU NIGHT OVER ALL THE AREA. -HOWERTON STRONG COLD FRONT WILL RACE SOUTH ACROSS THE REGION BETWEEN 06-09Z.
622 AM EDT WED APR 22 2015 HIGH PRESSURE WILL SHIFT OFF THE COAST BY THIS EVENING AND A WEAK COLD FRONT WILL MOVE THROUGH THE AREA EARLY THURSDAY WITH LIMITED MOISTURE.
633 AM EDT WED APR 22 2015 A COLD FRONT WILL BRING WIDESPREAD SHOWERS TO OUR REGION TODAY. QUIET FOR NOW BUT A SFC COLD FRONT IN ERN OHIO WILL MOVE EAST THROUGH NY AND PA TODAY. ONCE THERE THURSDAY THE LOW STALLS. FORCING BECOMES WEAK ON THE BACK SIDE OF THE LOW. REGARDING TO WHAT DEGREE OUR REGION EXPERIENCES PERIPHERAL INFLUENCES FROM THAT UPPER LOW. WITH 850MB TEMPERATURES A WAYS BELOW FREEZING. A COLD FRONT IS EXPECTED TO FOLLOW BEHIND THE TROUGH LATE THIS AFTERNOON.
A LARGE UPPER LEVEL LOW CURRENTLY OVER THE GREAT LAKES WILL SLOWLY MOVE NORTHEAST INTO EASTERN CANADA TONIGHT INTO TOMORROW WITH AN UPPER LEVEL RIDGE BUILDING INTO THE ROCKIES. WINDS WILL SHIFT TO THE NORTHEAST BEHIND THIS FRONT THEN TO MORE OF AN EASTERLY DIRECTION TOMORROW AS HIGH PRESSURE BUILDS INTO THE AREA. LOWS TONIGHT LOOK TO RANGE FROM THE LOWER TO MID 40S WITH HIGHS TOMORROW ONLY REACHING INTO THE LOWER TO MID 60S. AM NOT OVERLY EXCITED ABOUT THE PROSPECTS FOR MEASURABLE PRECIPITATION GIVEN THE UPPER RIDGE OVER THE REGION BUT WILL MAINTAIN SOME SMALL SLIGHT CHANCE POPS. BETTER CHANCES FOR PRECIPITATION WILL DEVELOP THURSDAY NIGHT AS THE UPPER RIDGE AXIS SHIFTS TO THE EAST AND WE SEE INCREASING SOUTHWEST FLOW ALOFT ALONG WITH SOME MID LEVEL WARM ADVECTION DEVELOPING OVER WESTERN KANSAS.
246 AM MDT WED APR 22 2015 A RIDGE WILL BE OVER THE ROCKIES THROUGH TONIGHT AND THEN SHIFT EAST INTO THE PLAINS THURSDAY.
IT WILL BE QUITE COOL WITH LOWS DIPPING INTO THE LOWER TO MID 30S.
HIGH PRESSURE OVER THE LOWER MISSISSIPPI VALLEY WITH WEAK H5 RIDGING JUST UPSTREAM AND AN H5 LOW OVER SOUTHERN CALIFORNIA MOVING UNDER THE WEST COAST RIDGE. WEAK ONSHORE FLOW SUPPORTED BY HIGH PRESSURE TO THE EAST WILL KEEP LOW LEVEL MOISTURE ELEVATED.
159 AM EDT WED APR 22 2015 HIGH PRESSURE WILL BUILD ACROSS THE REGION OVERNIGHT THROUGH EARLY WEDNESDAY.
UPPER AIR ANALYSIS LAST EVENING SHOWED ZONAL FLOW OVER TEXAS WITH A RIDGE TO THE WEST FROM NEW MEXICO TO THE NORTHERN ROCKIES AND A TROUGH ALONG THE WEST COAST. DEW POINT TEMPERATURES WERE IN THE LOWER TO MIDDLE 60S. THE UPPER LEVEL RIDGE WILL BUILD TO THE EAST DURING THIS PERIOD WITH THE RIDGE AXIS MOVING OVER EAST TEXAS BY THE END OF THE PERIOD. THE LOW LEVEL PATTERN WILL BE SIMILAR THURSDAY WITH STATIONARY BOUNDARY DRIFTING TO THE SOUTH AND THE DRYLINE FORMING AGAIN OVER WEST TEXAS.
A COLD FRONT WAS LOCATED FROM NEAR CLEVELAND TO ST LOUIS EARLY THIS MORNING.
442 AM CDT WED APR 22 2015 A COLD FRONT IS MAKING GOOD PROGRESS SOUTH ACROSS NORTHEAST OKLAHOMA AND FAR NORTHWEST ARKANSAS EARLY THIS MORNING. TEMPERATURES TODAY WILL STAY VERY COOL NORTH OF THE FRONTAL BOUNDARY AND MAY REMAIN EVEN COOLER THAN FORECAST IF THE RAIN PERSISTS TOO LATE INTO THE AFTERNOON.
NORTH OF A DEEP NEGATIVE ANOMALY/UPR TROF OVER ONTARIO/THE GREAT LAKES REGION.
236 AM MDT WED APR 22 2015 A PACIFIC TROUGH OFF THE NORTHWEST COMES ASHORE TODAY FORCING THE RIDGE OF HIGH PRESSURE EASTWARD OVER THE ROCKIES. A CLOSED LOW OFF THE SOUTHERN CALIFORNIA COAST WEAKLY PHASES WITH THE TROUGH TO THE NORTH AND ALSO MOVES INLAND. THE CLOSED LOW TO OUR SW WILL OPEN UP AS IT APPROACHES OUR CWA AND WILL BRING SOME ISOLATED PRECIP BRIEFLY THURSDAY NIGHT BEFORE DYING DOWN DUE TO LACK OF HEATING AND ANY REAL UPPER LEVEL SUPPORT.
09Z SURFACE ANALYSIS PLACES A COLD FRONT FROM SOUTHEAST MISSOURI BACK THROUGH NORTHWEST ARKANSAS AND NORTHEAST OKLAHOMA. TEMPERATURES ACROSS THE MID SOUTH ARE PREDOMINANTLY IN THE LOWER TO MIDDLE 50S AT MOST LOCATIONS.
The first wave of shower activity has developed overnight ahead of the cold front and is showing up on radar this morning moving northeast through eastern Oregon. However, the combination of daytime heating and the passage of the approaching cold front will initiate more widespread shower and thunderstorm activity over the southern Bitterroot/Sapphire & Anaconda/Pintler Mountains.
COOL HIGH PRESSURE WILL DOMINATE THE CENTRAL PLAINS TODAY BEHIND A COLD FRONT. AS HIGH PRESSURE RIDGING MOVES INTO THE MISSOURI VALLEY LATER TODAY AND TONIGHT, NORTHEAST WINDS OF 15 TO 25 MPH EARLY, BECOME LIGHT EASTERLY AROUND 10-12 MPH THIS AFTERNOON, THEN SOUTHEASTERLY UPSLOPE THIS EVENING. AM NOT OVERLY EXCITED ABOUT THE PROSPECTS FOR MEASURABLE PRECIPITATION GIVEN THE UPPER RIDGE OVER THE REGION BUT WILL MAINTAIN SOME SMALL SLIGHT CHANCE POPS. BETTER CHANCES FOR PRECIPITATION WILL DEVELOP THURSDAY NIGHT AS THE UPPER RIDGE AXIS SHIFTS TO THE EAST AND WE SEE INCREASING SOUTHWEST FLOW ALOFT ALONG WITH SOME MID LEVEL WARM ADVECTION DEVELOPING OVER WESTERN KANSAS.
338 AM CDT WED APR 22 2015 LATEST WATER VAPOR IMAGERY ALONG WITH EARLIER 00Z UPPER AIR ANALYSIS SHOWS AN UPPER TROUGH EXTENDING ALONG THE WEST COAST WITH A CLOSED CIRCULATION AT THE BASE OF THE TROUGH SPINNING OVER SOUTHERN CALIFORNIA. A LARGE LOW PRESSURE AREA REMAINS OVER ONTARIO AND THE GREAT LAKES REGION WITH A BROAD TROUGH EXTENDING SOUTH INTO THE EASTERN CONUS. LATEST MSAS SFC ANALYSIS SHOWS LARGE AREA OF HIGH PRESSURE EXTENDING SOUTH FROM THE CANADIAN PRAIRIE PROVINCES INTO THE CENTRAL PLAINS WITH A COLD FRONT ALONG THE KS/OK BORDER. THIS COULD ALLOW OVERNIGHT LOWS TO BOTTOM OUT IN THE LOWER 30S AGAIN WITH DRY/COOL AIRMASS STILL IN PLACE.
THE STRENGTH OF THE UPPER JET IS UNUSUAL, ROUGHLY 3 STANDARD DEVIATIONS ABOVE NORMAL, AND IS DRIVEN NOT ONLY BY THE BLOCKY H5 PATTERN ACROSS NORTH AMERICA, BUT ALSO BY THE UPPER RIDGE OVER THE CARIBBEAN WHICH HAS DELIVERED MANY OPPRESSIVELY WARM DAYS RECENTLY.
A FLAT SHORT WAVE RIDGE IN THE MID/UPPER LEVELS WILL BE OVER THE AREA TODAY. THE UPPER LOW OVER SOUTHERN CALIFORNIA MOVES SOUTHEAST INTO NORTHWEST MEXICO AND THE DOWNSTREAM RIDGE AMPLIFIES OVER THE REGION. LOW LEVEL FLOW VEERS TO SOUTHWEST AND THE LOW LEVEL MOISTURE DEPTH DIMINISHES TONIGHT INTO THURSDAY MORNING. WITH INCREASING CONVECTIVE INHIBITION UNDERNEATH THE AMPLIFYING RIDGE. TEMPERATURES WILL ALSO BE A BIT WARMER WITH READINGS IN THE 90S OVER THE BRUSH COUNTRY.
A WEAK COLD FRONT LOCATED FROM THE OH VALLEY WSWWD INTO THE CNTRL PLAINS CONTINUES TO GRADUALLY MOVE SWD. ANY ATTENDANT COLD FRONT THEN LOOKS TO MOVE SWD THROUGH THE AREA LATE SAT AFTERNOON/EVENING. AS HIGH PRESSURE BUILDS SWD INTO THE OH VALLEY/MID ATLANTIC STATES. WITH THE LATTER HALF OF THE GLOBAL MODELS INDICATING ANOTHER STRONG UPPER TROUGH PATTERN AND ATTENDANT COLD FRONT SWEEPING THROUGH THE REGION LATE MON AND INTO TUE. THIS AFTERNOON A WEAK COLD FRONT WILL MOVE ACROSS THE TENNESSEE VALLEY.
WITH THE LOWER MVFR CLOUD DECK ALONG THE RIO GRANDE. EXPECT THE LOWER MVFR CIGS WILL SPREAD NORTHEAST INTO THE COASTAL BEND BY 08-09Z.
AN UPPER LEVEL RIDGE WILL BE SLIDING OVER THE REGION TODAY. TWO SHORT WAVE DISTURBANCES WILL MOVE THROUGH THE WEAK RIDGE. TEMPS TODAY WILL BE A BIT COOLER THAN YESTERDAY DUE TO A SLIGHT DROP IN TEMPS ALOFT. UPPER TROUGH BEGINS TO MOVE EASTWARD THU. THOUGH IF LA JUNTA CYCLONE CAN DEEPEN ENOUGH TO WRAP SOME MOISTURE BACK WESTWARD. UPPER TROUGH THEN EJECTS EASTWARD ACROSS THE STATE THU NIGHT INTO FRI. BRIEF UPPER RIDGE EARLY SAT FOLLOWED QUICKLY BY INCREASING SW FLOW SAT AFTERNOON AS STRONG UPPER TROUGH DIGS INTO THE GREAT BASIN.
INTERESTING UPPER LEVEL PATTERN REMAINS OVER THE CONUS WITH A TROUGH/UPPER LOW OVER CALIFORNIA. RIDGING ACROSS THE PLAINS AND ANOTHER DEEP TROUGH OVER THE EASTERN U.
THE UPPER LEVEL TROUGH WILL CONTINUE TO NUDGE TOWARD THE COAST AS COOLER AIR SPREADS INLAND BEHIND THE COLD FRONT. THE MAIN UPPER LEVEL TROUGH IS FORECAST TO SWEEP ACROSS OUR FORECAST AREA WEDNESDAY NIGHT WITH THE AIR MASS STABILIZING OVERNIGHT.
341 AM CDT WED APR 22 2015 LARGE UPPER LOW OVER ONTARIO WILL CONTINUE TO SLOWLY PULL AWAY TODAY WITH SURFACE RIDGING APPROACHING FROM THE WEST. TEMPERATURES WILL CONTINUE TO HOLD BELOW NORMAL WITH THERMAL TROF STARTING OUT ACROSS THE STATE THIS MORNING THEN SHIFTING EASTWARD DURING THE DAY. TONIGHT THROUGH THURSDAY NIGHT WE WILL HAVE LITTLE CONCERN AS IOWA WILL BE IN BETWEEN RIDGING TO THE WEST AND THE DEPARTING LARGE LOW OVER THE EASTERN GREAT LAKES.
321 AM CDT WED APR 22 2015 COLD FRONT ALONG NORTHERN TIER OF COUNTIES AT THIS WRITING. AS HIGH PRESSURE WORKS INTO THE FA FROM THE NORTH/WEST IN THE WAKE OF THE DEPARTING FRONT. THE HIGH RIDGES OVERTOP THE TENNESSEE VALLEY TONIGHT. IT DRAWS DOWN COOLER AND DRIER AIR THROUGH THE COLUMN. THE HIGH FIRMS ITS GRIP ON THURSDAY.
THIS EVENING THROUGH WEDNESDAY NIGHT 20Z SURFACE ANALYSIS HAD BACK DOOR COLD FRONT FROM CENTRAL MT TO NORTH CENTRAL NE EVIDENCED BY PRESSURE RISE BUBBLE AND LINE OF CU/SC PER 1KM VISIBLE IMAGERY. COLD FRONT WILL SLOW DOWN AND STALL ACROSS THE FAR WESTERN REACHES OF THE CWA TONIGHT. IT WILL THEN MOVE BACK NORTHEAST SLOWLY WEDNESDAY AN UPPER LEVEL RIDGE OVER THE ROCKIES SHIFTS EASTWARD.
ANOTHER LOW PRESSURE SYSTEM WILL MOVE SOUTH ALONG THE COAST THROUGH THE END OF THE WEEK.
A SPLIT FLOW REGIME CONTINUES ACROSS NORTH AMERICA THIS MORNING WITH A HIGHLY AMPLIFIED TROUGH DOMINATING THE EASTERN 2/3 OF THE CONTINENT AND A LOW CUTTING OFF OVER SOUTHERN CALIFORNIA. SURFACE ANALYSIS SHOWS YESTERDAY'S COLD FRONT OVER SOUTH FLORIDA WITH HIGH PRESSURE CENTERED OVER OUR FORECAST AREA.
THE HIGH CLOUDS SHOULD NOT HAVE TOO MUCH AFFECT ON CURRENT PROJECTED LOWS. /39 DRY HIGH PRESSURE WILL HOLD OVER THE CWA THROUGH TONIGHT. HOWEVER THE NEXT SHORT WAVE AND ASSOCIATED COLD FRONT OVER THE MIDWEST WILL SPREAD MID AND HIGH LEVEL CLOUDS OVER THE REGION LATE TONIGHT AND WEDNESDAY.