Aikyam-Lab/Synoptic-Bench huggingface dataset:
A large upper level low remains cut off and in place over the Missouri River Valley/Plains and is very slow to progress. Proximity to the low and some influence with diurnal heating will keep the thunder potential in place, even if minimal. But the potential for rain will remain in place in the region until the low moves out to the northeast tomorrow. Fairly dry conditions are likely to start the day Thursday, but precipitation chances will increase during the afternoon as the upper low remnants cross Illinois and diurnal instability is at a maximum (although only a few hundred J/KG of CAPE are anticipated).
1137 PM CDT WED APR 20 2016 We are currently watching scattered showers/few tstorms develop and move across the western part of the CWA due to perturbations associated with an upper level low over Nebraska. As the center of the upper low moves into the western IA later today and into this evening, this area of scattered convection will shift across the area from west to east. With the main trough associated with closed low in the upper Midwest pivoting toward the area. Dry weather will continue into Friday, but depending on the exact track of the aforementioned upper low. Temperatures have been tricky today with highs in the lower 80s with sunshine in the east. We will see highs on Thursday and Friday in the lower to possibly mid 70s. and an upper level ridge over the central U.
EVENTUALLY A COLD FRONT WILL BEGIN TO AFFECT TAFS FROM WEST TO EAST WITH VFR VCSH CONDITIONS LATE IN THE PERIOD.
1147 PM CDT WED APR 20 2016 PARENT UPPER LOW CONTINUES TO SPIN/WOBBLE ACROSS NEBRASKA. THE UPPER LOW WHICH HAS AFFECTED MID-AMERICA FOR DAYS WILL FINALLY PROGRESS EAST THURSDAY. WITH SURFACE AND UPPER RIDGING SUPPORTING SUNNY SKIES.
Upper ridge over the Ohio Valley continues to flatten, with a closed and vertically stacked low now over eastern Nebraska poised to be the main player in our short-term weather. Main challenge will be timing of precip as the low tries to open up and move eastward. Southern stream impulse is helping to drive convection over the Lower Mississippi Valley, and as it lifts northeast we should see precip spread into west-central KY and southwestern IN as the night progresses. Will begin Thursday evening with likely POP, but taper down from west to east as the surface front and main upper trof axis push through.
/ISSUED 448 PM EDT WED APR 20 2016/ HIGH PRESSURE REMAINS IN PLACE ACROSS THE FLORIDA PENINSULA AND ADJACENT WATERS. THE GLOBAL MODELS CONTINUE TO INDICATE A COLD FRONT ENTERING THE SOUTHEASTERN STATES FRIDAY WITH SOUTHERLY LOW LEVEL FLOW CONTINUING TO BRING DEEP LAYERED MOISTURE INTO THE REGION. IN ADDITION A MID TO UPPER LEVEL TROUGH WILL DIG INTO THE CENTRAL AND EASTERN GULF.
A VORT LOBE SWINGING AROUND THE BASE OF AN UPPER LOW SWINGING EAST OVER THE MID-MISSISSIPPI RIVER VALLEY WILL PUSH A WEAK SURFACE BOUNDARY TOWARDS THE FA. WITH THE RESULT BEING A MORE ORGANIZED ON- SHORE FLOW OVER THE LOWER MISSISSIPPI RIVER VALLEY AND SOUTHEASTERN CONUS.
A LARGE UPPER LEVEL LOW PRESSURE SYSTEM CONTINUES TO SPIN OVER THE CENTRAL PLAINS STATES THIS EVENING AND WILL MOVE LITTLE THROUGH THE NIGHT. LOW TEMPERATURES SHOULD REMAIN IN THE LOWER 60S IN MOST LOCATIONS OVERNIGHT BENEATH MOIST LOW LEVEL SOUTHERLY FLOW. A HIGHLY AMPLIFIED BUT POSITIVELY TILTED LONGWAVE TROUGH WILL SHIFT OUT OF THE PLAINS SHIFTING ACROSS THE MISSISSIPPI RIVER VALLEY TOMORROW NIGHT. DEW POINTS WILL BE IN THE LOW 60S SO A STRONG TO SEVERE STORM CANNOT BE RULED OUT. FEEL LIKE THE HIGHER THREAT FOR STRONG OR SEVERE STORMS WILL REMAIN TO OUR SOUTH AND WEST WHERE DEW POINTS WILL CLIMB INTO THE MIDDLE 60S. AS THE TROUGH SHIFTS ACROSS MIDDLE TENNESSEE AND ALABAMA.
A WEAK COLD FRONT WILL PASS THROUGH THE REGION KEEPING NORTH WINDS ACROSS MOST OF THE REGION DURING THE DAY. THE MAIN IDEA PER LATEST REGIONAL RADAR TRENDS WAS HOLD THE HIGHEST RAIN CHANCES ACROSS THE WESTERN HALF OF THE AREA. SLIGHTLY COOLER LOW TEMPERATURES ACROSS THE NORTH WHERE TEMPERATURES HAVE ALREADY FALLEN INTO THE 50S ACROSS MANY AREAS.
IR/WV SATELLITE THIS EVENING HAS A GOOD DEPICTION OF THE CLOSED LOW ACROSS THE CENTRAL US. SHOWERS FORMING ALONG THE CONVERGENCE OF THE DECAYING HIGH PRESSURE SYSTEM AND THE FRONT ASSOCIATED WITH THE LOW HAVE FOR THE MOST PART BEEN STAGNANT OVER THE MS RIVER VALLEY. EXPECT A SLOW INCREASE IN ACTIVITY FROM WEST TO EAST THURSDAY MORNING WITH MUCH OF THE ACTIVITY OCCURRING TOMORROW AFTERNOON/EVENING AS THE CLOSED LOW OPENS UP AND SHIFTS EASTWARD. DUE TO BOTH SLOW MOTION OF UPPER TROUGH RESPONSIBLE FOR PRECIP TO THE WEST AND LINGERING LAYER OF DRY AIR NEAR THE SFC.
HIGH PRESSURE IN CONTROL WITH SOUTHEAST FLOW INCREASING OVER MARINE AREA AS CENTER OF HIGH SHIFTS FURTHER TO THE EAST. WILL OPT OUT OF THIS SCENARIO DUE TO FAIRLY STRONG SUBSIDENCE IN PROXIMITY TO RIDGE AXIS AND LOW LEVELS REMAINING VERY DRY.
630 PM CDT WED APR 20 2016 PARENT UPPER LOW CONTINUES TO SPIN/WOBBLE ACROSS NEBRASKA. THE UPPER LOW WHICH HAS AFFECTED MID-AMERICA FOR DAYS WILL FINALLY PROGRESS EAST THURSDAY. WITH SURFACE AND UPPER RIDGING SUPPORTING SUNNY SKIES.
CURRENT SURFACE ANALYSIS PLACES COLD FRONT DROPPING THROUGH THE SOUTHERN PRAIRIE PROVINCES WILE RIDGE REMAINS OVER THE CENTRAL ROCKIES. WHILE RIDGE PUSHES INTO THE FAR NORTHERN PLAINS. AFOREMENTIONED COLD FRONT WILL GRADUALLY SAG INTO THE AREA WITH SOME BREEZY CONDITIONS POSSIBLE IN ITS WAKE. BREEZY CONDITIONS MAY CONTINUE OVER EASTERN LOCATIONS IN THE WAKE OF THE COLD FRONT. TEMPERATURES WILL BE COOLER MAINLY OVER EASTERN LOCATIONS AS COOL AIR WORKS INTO THE AREA BEHIND THE FRONT. UPPER LEVEL RIDGING BUILDS INTO THE AREA BRINGING WARMING TEMPERATURES TO THE AREA TO END THE WEEK.
822 PM CDT WED APR 20 2016 A large upper level low pressure was centered near Omaha, Nebraska this evening. Storms have developed during the afternoon on the High Plains. More sunshine will result in warmer daytime temperatures over the next few days.
/issued 228 PM CDT WED APR 20 2016/ Over the past 24 hours, the upper pattern has become more progressive with the upper low finally making its way into the northern plains. The best chance for convection through this evening will be across the Lower Trans Pecos/Stockton Plateau, where a couple of storms have already developed as of 2PM CDT along a lingering outflow boundary from last night's convection. As cooler air filters in behind the front, temperatures Thursday are expected to be in the 70s to lower 80s, with a few readings in the lower 90s in the Rio Grande Valley. Ridging builds over the region on Friday allowing temperatures to moderate, with just a slight chance of showers and thunderstorms, mainly confined to the higher terrain and the Big Bend Area.
BEFORE LOW PRESSURE BRINGS INCREASING CLOUD COVERAGE AND THE POSSIBILITY OF RAIN SHOWERS INTO FRIDAY. DRY AND MILD OVERNIGHT AS RIDGING TRANSITIONS OVER AND EAST OF THE FORECAST AREA. WITH THE RIDGE AXIS TO THE EAST. SOUTHWEST LOW LEVEL FLOW WILL BEGIN TO INCREASE THURSDAY AS CLOSED UPPER LEVEL LOW OVER NEBRASKA BEGINS TO SHIFT EAST AND OPEN. UPPER LEVEL TROUGH AND ASSOCIATED LOW PRESSURE WILL SLOWLY MOVE ACROSS THE SOUTHERN GREAT LAKES THROUGH FRIDAY WITH SHOWERS AND AN ISOLATED THUNDERSTORM. COLD FRONTAL PASSAGE ON THE BACKSIDE OF THE SYSTEM WILL DIMINISH SHOWERS FRIDAY AFTERNOON AND EVENING WITH COOLER AIR WORKING INTO THE REGION.
1007 PM EDT WED APR 20 2016 WARM FRONT PASSES TO THE WEST. PRECIPITATION CHANCES INCREASE FOR SECOND HALF OF THE WEEK WITH AN UPPER LEVEL LOW/COLD FRONT. HIGH PRESSURE FOR THE WEEKEND. WARM FRONT PASSES TO OUR WEST WITH A SUBTLE INCREASE IN INSTABILITY OVER THE SOUTH AND WESTERN PARTS OF OUR FORECAST AREA THIS AFTERNOON. A WARM NIGHT TONIGHT IN WARM SECTOR BEFORE A COLD FRONT APPROACHES FROM THE WEST INCREASING CHANCES FOR RAIN. MORE NUMEROUS SHOWERS AND THUNDERSTORMS FRIDAY AS UPPER LOW ACROSS THE PLAINS OPENS INTO A WAVE AND PUSHES EAST ACROSS THE AREA. AND SURFACE COLD FRONT MOVES THROUGH THE REGION.
A WARM FRONT RAN FROM THE LOW INTO SOUTHEAST IOWA AND THEN CENTRAL ILLINOIS. A COLD FRONT RAN FROM THE LOW SOUTH INTO CENTRAL MISSOURI.
THE MAIN IDEA PER LATEST REGIONAL RADAR TRENDS WAS HOLD THE HIGHEST RAIN CHANCES ACROSS THE WESTERN HALF OF THE AREA. SLIGHTLY COOLER LOW TEMPERATURES ACROSS THE NORTH WHERE TEMPERATURES HAVE ALREADY FALLEN INTO THE 50S ACROSS MANY AREAS.
Center of the upper low was located over eastern Nebraska with a lobe of energy rotating south and southeast out of western Nebraska into northwest and north central Kansas. With the upper trough forecast to move across northeast Kansas tonight, have maintained slight chances of showers. Tonight clouds may decrease with loss of heating, but expect clouds to move back in with the upper trough moving through. Most of the area should remain wrapped in clouds on the back side of the upper low as moisture advects across northeast and east central Kansas. Highs Thursday will range from the mid 60s far north to the lower 70s near central Kansas despite northwest winds and cool advection.
PRECIPITATION ALONG THE COLD FRONT WILL MOVE INTO THE TERMINALS JUST BEYOND THIS TAF CYCLE AND WILL BE ADDED IN LATER TAF ISSUANCES.
804 PM EDT WED APR 20 2016 SCT-BKN HIGH CLOUDS ACROSS THE AREA UNDER HIGH PRESSURE. A SLIGHTLY WARMER NIGHT ON TAP WITH LOWS ON TRACK TO FALL INTO THE UPPER 50S NORTH. ALSO REMOVED THE LOW RAIN CHANCES OVER THE SOUTHERN WATERS FOR THIS EVENING.
704 PM CDT WED APR 20 2016 NORTHWEST FLOW ALOFT WITH AN UPPER LEVEL LOW PRESSURE TROUGH EXPECTED TO PASS JUST NORTH OF THE AREA OVERNIGHT. SURFACE WINDS WILL TURN NORTH TO NORTHEAST BEHIND A SURFACE OUTFLOW/COLD FRONT BOUNDARY AND LIKELY TO SPREAD MOSTLY A LOW MVFR CLOUD LAYER BACK INTO THE TERMINALS OVERNIGHT INTO EARLY THURSDAY. UPPER RIDGE WILL BEGIN BUILDING ON THURSDAY WITH EVENTUAL TURN TO VFR EXPECTED. COOLER. A MID LEVEL SPEED MAX ROTATING AROUND THE PERSISTENT UPPER LOW THAT THIS AFTERNOON IS DRIFTING EWD OVER THE CENTRAL HIGH PLAINS. WINDS WILL GRADUALLY VEER BACK TO THE SOUTH BY FRIDAY AFTERNOON AS A LEE TROF DEVELOPS CREATING THE BEGINNINGS OF WHAT WILL BE BREEZY DAYS AHEAD.
THERE MAY BE A FEW LINGERING CLOUDS ALONG AND SOUTH OF THE HIGHWAY 200 CORRIDOR. MEANWHILE MAIN FCST CHALLENGE WILL BE COLD FRONT THAT WILL BE DROPPING SOUTH OVERNIGHT. EXPECT A SHARP COLD FRONT WITH A SHARP WIND CHANGE TO THE NORTH AND INCREASE IN SPEED TO REACH THE INTL BORDER IN THE 04Z TIME FRAME AND RACE SOUTH EXITING THE SRN FCST AREA BY 12Z. FRIDAY WILL SEE LIGHT WINDS IN THE MORNING TURNING EAST-SOUTHEAST IN THE AFTN AHEAD OF A WEAK SHORT WAVE/TROUGH WHICH WILL MOVE SOUTHEAST THRU SRN MANITOBA INTO FAR NRN MN FRIDAY NIGHT.
UPPER TROUGH/SHORT WAVE SWEEPS ACROSS THURSDAY NIGHT THROUGH FRIDAY NIGHT.
1052 PM EDT WED APR 20 2016 WARM FRONT PASSES TO THE WEST. PRECIPITATION CHANCES INCREASE FOR SECOND HALF OF THE WEEK WITH AN UPPER LEVEL LOW/COLD FRONT. HIGH PRESSURE FOR THE WEEKEND. WARM FRONT PASSES TO OUR WEST WITH A SUBTLE INCREASE IN INSTABILITY OVER THE SOUTH AND WESTERN PARTS OF OUR FORECAST AREA THIS AFTERNOON. A WARM NIGHT TONIGHT IN WARM SECTOR BEFORE A COLD FRONT APPROACHES FROM THE WEST INCREASING CHANCES FOR RAIN. MORE NUMEROUS SHOWERS AND THUNDERSTORMS FRIDAY AS UPPER LOW ACROSS THE PLAINS OPENS INTO A WAVE AND PUSHES EAST ACROSS THE AREA. AND SURFACE COLD FRONT MOVES THROUGH THE REGION.
THE UPPER LOW THAT WAS OVER THE MID WEST WILL FINALLY EXIT EASTWARD ON THURSDAY AND THURSDAY NIGHT.
A WARM FRONT EXTENDED FROM BLACK RIVER FALLS WISCONSIN TO MASON CITY IOWA. THERE WERE SCATTERED SHOWERS ASSOCIATED WITH THIS WARM FRONT. THE UPPER LEVEL LOW WILL PRODUCE ADDITIONAL SHOWERS AS IT MOVES EAST ACROSS THE AREA. HIGH PRESSURE WILL BUILD ACROSS THE AREA ON THURSDAY NIGHT.
1055 PM EDT WED APR 20 2016 HIGH PRESSURE OVER NEW YORK STATE WILL MOVE INTO THE MID ATLANTIC TONIGHT BEFORE SLIDING OFFSHORE THURSDAY. A COLD FRONT WILL MOVE THROUGH THE REGION FRIDAY. HIGH PRESSURE RETURNS FOR THE WEEKEND. HIGH PRESSURE CONTINUES TO SLIDE EAST-SOUTHEAST AWAY FROM THE AREA THIS EVENING. TEMPS WL BE A FEW DEGS WARMER THAN TDA - HIGHS IN THE LM70S. THU NGT WL BE WARMER W/ LOWS IN THE MU50S. COLD FRONT APPROACHES FROM THE NORTH ON MON AND BECOMES STATIONARY OVER OUR REGION INTO TUE. SUB-VFR CONDITIONS POSSIBLE ON MON AND TUE AS COLD FRONT APPROACHES AND LINGERS OVER OUR REGION BRINGING A CHANCE OF SHOWERS. THINK MOST GUSTS WILL BE NEAR-SHORE GIVEN THE WARMER AIR OVER THE COOLER WATER SHOULD LIMIT GUSTS OVER THE OPEN BAY.
INCREASING MOISTURE AND A COLD FRONT WILL MOVE BRINGING A CHANCE OF SHOWERS AND A FEW THUNDERSTORMS.
508 PM PDT WED APR 20 2016 The onshore flow will increase overnight into friday bringing increasing low clouds and fog and cooler temperatures. Increasing onshore flow expected through Friday as a couple of troughs move through the northern half of the state. A 7mb onshore lax-dag gradient will push cooler maritime air much farther inland than it has the last couple days so most areas should see highs at least 3-6 degrees cooler than today. Low cloud coverage will continue to expand across the bight Thu afternoon and evening and should push well into the valleys Thu night as the second and deepest of the troughs moves into nrn CA.
WARM HIGH PRESSURE WILL REMAIN OVER THE REGION THROUGH THURSDAY THEN SHIFT EAST FRIDAY AHEAD OF A PACIFIC STORM.
DRY AND WARMER WEATHER WILL GRACE NORTHERN ARIZONA THROUGH THURSDAY UNDER HIGH PRESSURE ALOFT. A SERIES OF WEATHER SYSTEMS WILL BRUSH ARIZONA PRODUCING GUSTY WINDS AND COOLER TEMPERATURES ALONG WITH THE POTENTIAL FOR SHOWERS. HIGH PRESSURE IS BUILDING OVER ARIZONA THIS AFTERNOON. HIGH PRESSURE WILL CONTINUE TO BUILD OVER ARIZONA AND MOVE EAST BY THURSDAY NIGHT. THE WARMER TEMPERATURES WILL GENERATE AFTERNOON SOUTHWEST WINDS OF 10 TO 20 MPH. FAIRLY CONFIDENT THAT WINDY CONDITIONS (SOUTHWEST TO WEST) AND COOLER TEMPERATURES ARE IN STORE OVER THIS PERIOD.
WITH THE LARGE RIDGE OFF TO THE WEST. SCT SYNOPSIS: A LARGE CLOSED LOW SETS OVER THE GREAT PLAINS OF THE CONUS WHILE A LARGE RIDGE RUNS FROM THE BAJA THROUGH NEVADA THE PACIFIC NORTHWEST AND THEN TURNS INLAND OVER SOUTHERN SASKATCHEWAN THROUGH ONTARIO. A SURFACE FRONT/DENSITY DISCONTINUITY EXISTS BEHIND THE RIDGE AXIS OVER SOUTHERN CANADIAN PRAIRIE PROVINCES. RIDGE INFLUENCE TO THE FAR WEST WILL BECOME DOMINANT.
WATER VAPOR SATELLITE IMAGERY SHOWS A PLUME OF MID AND HI LEVEL MOISTURE ADVECTING WESTWARD OVER THE CWA IN THE NORTHWEST QUAD OF THE LOW. EXPECT WE WILL DRY OUT QUICKLY OVERNIGHT AS THE UPPER LOW PUSHES EASTWARD AND LARGE SCALE RIDGING BUILDS IN FROM THE WEST. SO EXPECT A TREND TOWARD WARMER WEATHER AS WE HEAD INTO THE LATTER HALF OF THE WEEK W/ HIGHS LIKELY IN THE 60S AND 70S OVER MUCH OF THE AREA. WARM AND DRIER TREND EXPECTED TO CONTINUE INTO FRIDAY AS UPPER RIDGING MOVES ACROSS THE CENTRAL ROCKIES.
/ISSUED 704 PM CDT WED APR 20 2016/ NORTHWEST FLOW ALOFT WITH AN UPPER LEVEL LOW PRESSURE TROUGH EXPECTED TO PASS JUST NORTH OF THE AREA OVERNIGHT. SURFACE WINDS WILL TURN NORTH TO NORTHEAST BEHIND A SURFACE OUTFLOW/COLD FRONT BOUNDARY AND LIKELY TO SPREAD MOSTLY A LOW MVFR CLOUD LAYER BACK INTO THE TERMINALS OVERNIGHT INTO EARLY THURSDAY. UPPER RIDGE WILL BEGIN BUILDING ON THURSDAY WITH EVENTUAL TURN TO VFR EXPECTED. COOLER. A MID LEVEL SPEED MAX ROTATING AROUND THE PERSISTENT UPPER LOW THAT THIS AFTERNOON IS DRIFTING EWD OVER THE CENTRAL HIGH PLAINS. WINDS WILL GRADUALLY VEER BACK TO THE SOUTH BY FRIDAY AFTERNOON AS A LEE TROF DEVELOPS CREATING THE BEGINNINGS OF WHAT WILL BE BREEZY DAYS AHEAD.
Parent upper low will finally phase with the larger scale pattern by the end of the week, allowing for a progressiveness of the weather, but not before periodic rain chances persist through tomorrow. Upper-level ridging will then briefly take control into the weekend, allowing for dry conditions and warming temps.
WILL GO WITH THE HIGHEST POPS ACROSS THE WESTERN PORTIONS OF THE CWA WITH LOWER POPS TOWARDS THE COAST THIS EVENING. THE FORECAST FOR THURSDAY AND THURS NIGHT IS CHALLENGING WITH THE WEST TO NORTHWEST FLOW ALOFT BUT THE NAM AND GFS HAVE A CONVECTIVE BOUNDARY DEVELOPING ACROSS PORTIONS OF CENTRAL TX THURSDAY AND AS THIS FEATURE MOVES SOUTHWARD IT WILL PROVIDE A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS ACROSS PORTIONS OF THE CWA THURSDAY INTO THURS NIGHT AS MOISTURE POOLS ALONG AND AHEAD OF A WEAK COLD FRONT MOVES SOUTHWARD ACROSS SOUTH TX.
A WIDER RIDGE TO VALLEY TEMPERATURE DIFFERENCE WAS ADDED TO PORTIONS OF THE KY. KY MESONET OBSERVATIONS FORM ACROSS THE REGION INDICATE THIS IS TAKING PLACE WITH SOME OF THE NORMALLY COLDER SPOTS ALREADY IN THE UPPER 60S WHILE RIDGES ARE IN THE MID AND UPPER 70S. TODAY HAS BEEN MUCH WARMER AND DRIER THAN MODELS INDICATED DUE TO THE LACK OF CLOUD COVER. A CU FIELD IS FINALLY STARTING TO FORM OVER PORTIONS OF THE AREA AS A LOW PRESSURE SYSTEM SLOWLY MAKES ITS WAY TOWARDS CENTRAL KENTUCKY. AS THE LOW PRESSURE SYSTEM MOVES INTO IN/IL AROUND 00Z FRIDAY. MODELS ARE INCONSISTENT WITH THE AMOUNT OF MOISTURE AND FORCING AS THE COLD FRONT PASSES.
Overnight lows will range from around 40 except warmer southeast of Dodge around 40 to 45 degrees. For Friday, dry and warm conditions expected on Friday as upper ridging moves into the Plains.
1145 PM CDT WED APR 20 2016 EARLY AFTERNOON WATER VAPOR IMAGERY INDICATED THE CENTER OF THE UPPER LOW WAS LOCATED OVER E-CNTRL NEB/W-CNTRL IA AND WAS BECOMING VERTICALLY STACKED. ONCE THIS SYSTEM EXITS TO THE SOUTHEAST ON THURSDAY HEIGHT RISES AND WARMER TMPS SHOULD BE THE STORY HEADING INTO THE WEEKEND.
1118 PM EDT WED APR 20 2016 HIGH PRESSURE REMAINS IN PLACE OVER THE REGION TONIGHT AND SHIFTS SLOWLY EAST THURSDAY. A COLD FRONT APPROACHES FROM THE WEST THURSDAY NIGHT AND FRIDAY AND COULD SET OFF SOME SHOWERS. COOLER AND DRIER HIGH PRESSURE MOVES IN FOR THE WEEKEND.
THE 19Z MSAS SURFACE ANALYSIS SHOWED AN AREA OF LOW PRESSURE SITUATED OVER WEST-CENTRAL IA WITH A COLD FRONT EXTENDED SOUTHWARD. AN INVERTED TROUGH STRETCHED NORTHWEST AND A WARM FRONT EXTENDED E-SE INTO CENTRAL IL. MILD CONDITIONS TONIGHT WITH MIN TEMPERATURES IN THE LOWER TO MIDDLE 40S NORTH/LAKESHORE. GENERAL TROFFINESS AND COOLER TEMPS ALOFT ARE EXPECTED TO PRODUCE MORE SHOWERS OVER NE WI.
1044 PM CDT WED APR 20 2016 LARGE AND SLOW MOVING UPPER LOW WILL CONTINUE TO WOBBLE EASTWARD THROUGH EASTERN NEBRASKA AND WESTERN IOWA TONIGHT AND THURSDAY. SOUTH CENTRAL SD INTO THE HIGHWAY 14 CORRIDOR IN SOUTH DAKOTA WILL REMAIN LARGELY OUTSIDE OF THE MORE PERSISTENT RAINFALL. LATEST MODEL RUNS ARE MUCH SLOWER IN EXITING THE UPPER LOW. UPPER RIDGING DOMINATES ACROSS THE WESTERN PLAINS AND FRONT RANGE OF THE ROCKIES. ALLOWING CHILLY HIGH PRESSURE TO FILTER DOWN INTO THIS FORECAST AREA DOWN THE FRONT SIDE OF THE UPPER RIDGE. HAVE NO SUB FREEZING TEMPERATURES IN THE AREA.
939 PM EDT WED APR 20 2016 HIGH PRESSURE OVER NEW YORK STATE WILL MOVE INTO THE MID ATLANTIC TONIGHT BEFORE SLIDING OFFSHORE THURSDAY. A COLD FRONT WILL MOVE THROUGH THE REGION FRIDAY. HIGH PRESSURE RETURNS FOR THE WEEKEND. HIGH PRESSURE CONTINUES TO SLIDE EAST-SOUTHEAST AWAY FROM THE AREA THIS EVENING. TEMPS WL BE A FEW DEGS WARMER THAN TDA - HIGHS IN THE LM70S. THU NGT WL BE WARMER W/ LOWS IN THE MU50S. COLD FRONT APPROACHES FROM THE NORTH ON MON AND BECOMES STATIONARY OVER OUR REGION INTO TUE. SUB-VFR CONDITIONS POSSIBLE ON MON AND TUE AS COLD FRONT APPROACHES AND LINGERS OVER OUR REGION BRINGING A CHANCE OF SHOWERS. THINK MOST GUSTS WILL BE NEAR-SHORE GIVEN THE WARMER AIR OVER THE COOLER WATER SHOULD LIMIT GUSTS OVER THE OPEN BAY.
SHORT WAVE TROUGH MOVING NNE THROUGH OREGON THIS AFTERNOON WILL SET OFF SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS IN HARNEY COUNTY AND WRN-MOST BAKER COUNTY LATE TODAY AND THIS EVENING. THURSDAY NIGHT AND FRIDAY A DEEP UPPER TROUGH FROM THE GULF OF ALASKA WILL MOVE ONSHORE IN OREGON AS A CLOSED LOW. THE LOW WILL SPREAD SHOWERS AND A SLIGHT CHANCE OF THUNDERSTORMS ACROSS OREGON AND THEN INTO IDAHO DURING THE DAY. OREGON ZONES WILL COOL SIGNIFICANTLY FRIDAY AS THE UPPER LOW TRACKS DIRECTLY OVER THEM.
845 PM PDT WED APR 20 2016 HIGH PRESSURE WILL CONTINUE TO PROVIDE DRY AND UNSEASONABLY WARM CONDITIONS THROUGH THURSDAY. INCREASED WINDS AND A LITTLE COOLER THAN NORMAL TEMPERATURES. A WEAK UPPER TROUGH CONTINUES TO LIFT NORTHEAST OVER THE NORCAL TODAY WITH JUST SOME HIGH CIRRUS CLOUDS SPREADING ACROSS THE DISTRICT. LITTLE CHANGE IS EXPECTED ON THURSDAY AS THE LOW MOVES AWAY LEAVING A DRY SOUTHWESTERLY FLOW ALOFT OVER REGION. A MORE SIGNIFICANT CHANGE IS COMING ON FRIDAY AS AN UPPER LOW DROPS DOWN FROM THE NE PACIFIC.
1026 PM EDT WED APR 20 2016 CURRENTLY - A HIGH PRESSURE CELL IS MOVING SOUTHEASTWARD OFF THE MID ATLANTIC COAST. WITH DEW POINTS IN THE LOWER 60S AND TEMPERATURES SLIDING INTO THE LOWER 70S. SHORT TERM - MODERATE EASTERLY BREEZES WILL CONTINUE OVERNIGHT AS HIGH PRESSURE CONTINUES TO CONSOLIDATE NORTH OF THE BAHAMAS. HIGH PRESSURE MOVING SOUTHEASTWARD OFF THE MID ATLANTIC COAST IS GRADUALLY INCREASING WINDS ACROSS KEYS WATERS.
/ISSUED 822 PM CDT WED APR 20 2016/ A large upper level low pressure was centered near Omaha, Nebraska this evening. Storms have developed during the afternoon on the High Plains. More sunshine will result in warmer daytime temperatures over the next few days.
UPPER LEVEL HIGH PRESSURE RIDGE REMAINS OVER THE NORTHERN ROCKY MOUNTAIN REGION TONIGHT THROUGH LATE THURSDAY. BROAD HIGH PRESSURE RIDGE THAT WAS CENTERED OVER WA/OR/ID PANHANDLE LAST COUPLE DAYS NOW EXTENDS ACROSS THE TREASURE STATE, BRINGING PLENTY OF FAIR SKIES AND WARMER THAN NORMAL TEMPERATURES. SIMILARLY, OVERNIGHT LOWS WILL BE QUITE MILD AS MOST LOWER ELEVATION SITES ONLY COOL INTO THE LOW-MID 40S. LATEST FORECAST MODELS ARE STILL HINTING THAT SOME SPOTTY MOISTURE MAY WORK ITS WAY INTO THE WEST SIDE OF THE RIDGE ON FRI AFTN/EVE.
607 PM CDT WED APR 20 2016 LARGE AND SLOW MOVING UPPER LOW WILL CONTINUE TO WOBBLE EASTWARD THROUGH EASTERN NEBRASKA AND WESTERN IOWA TONIGHT AND THURSDAY. SOUTH CENTRAL SD INTO THE HIGHWAY 14 CORRIDOR IN SOUTH DAKOTA WILL REMAIN LARGELY OUTSIDE OF THE MORE PERSISTENT RAINFALL. LATEST MODEL RUNS ARE MUCH SLOWER IN EXITING THE UPPER LOW. UPPER RIDGING DOMINATES ACROSS THE WESTERN PLAINS AND FRONT RANGE OF THE ROCKIES. ALLOWING CHILLY HIGH PRESSURE TO FILTER DOWN INTO THIS FORECAST AREA DOWN THE FRONT SIDE OF THE UPPER RIDGE. HAVE NO SUB FREEZING TEMPERATURES IN THE AREA.
Any clearing will be fairly short lived however, as another lobe of vorticity rounds the base of the upper low toward sunrise. Showers and a few isolated rumbles of thunder will again be possible across portions of the Ozarks during the day Thursday as the slow moving upper level low finally swings northeast of the region taking the clouds and rain with it.
FORECAST CHALLENGES INCLUDE HOW FAR NORTH THE CURRENT PRECIP SHIELD COULD DRIFT THIS EVENING ALONG WITH TIMING A DRY COLD FRONTAL PASSAGE SOUTHWARD THROUGH THE CWA THURSDAY MORNING. GENERALLY LIGHT AND VARIABLE WINDS WILL SWITCH AROUND TO THE NORTH BY EARLY THURSDAY MORNING IN RESPONSE TO THE PASSAGE OF A COLD FRONT WORKING IN FROM THE NORTH. AND WHERE FORECAST RELATIVE HUMIDITY VALUES ARE THE HIGHEST /MAINLY THE EASTERN THIRD OF THE CWA/. LOW TEMPERATURES ARE FORECAST TONIGHT TO DROP INTO THE LOW TO MID 40S WHILE HIGH TEMPERATURES ON THURSDAY ARE EXPECTED TO RANGE ANYWHERE FROM THE UPPER 50S ACROSS THE FAR NORTHEAST CWA /COLDEST CAA IMPACT/ TO THE UPPER 60S ACROSS THE FAR SOUTHWESTERN CWA.
Lows tonight will be mainly in the lower 60s, with highs Thursday in the mid and upper 70s.
CHATTANOOGA AIRPORT, TN 59 78 60 74 / 10 30 70 60 KNOXVILLE MCGHEE TYSON AIRPORT, TN 58 78 58 73 / 20 30 70 70 OAK RIDGE, TN 58 78 58 73 / 10 30 70 60 TRI CITIES AIRPORT, TN 51 78 56 72 / 10 20 60 70.
MID/UPPER LEVEL RIDGE BEGINS TO MOVE INTO THE AREA WITH DRY CONDITIONS AND PLENTY OF SUNSHINE EXPECTED. LATEST GUIDANCE SUPPORTED MAKING ONLY MINOR ADJUSTMENTS IN THE HIGH TEMPERATURES WITH READINGS EXPECTED FROM THE MIDDLE 60S TO THE LOWER 70S.
1232 AM EDT THU APR 21 2016 HIGH PRESSURE WILL CROSS THE REGION OVERNIGHT THROUGH THURSDAY. LOW PRESSURE WILL CROSS THE AREA FRIDAY. HIGH PRES RIDGING ACROSS THE CWA DURING THE DAY ON THURSDAY W/WINDS TURNING MORE WESTERLY. A SPECIAL WEATHER STATEMENT MIGHT BE THE WAY TO GO AS WAS THE CASE TODAY HIGHLIGHTING THE HIGH FIRE DANGER.