Aikyam-Lab/Synoptic-Bench huggingface dataset:
1146 PM EST FRI NOV 13 2015 AVIATION WINDS WILL DIMINISH TONIGHT AND SCATTERED RAIN AND SNOW SHOWERS WILL END AS LOW PRESSURE DEPARTS. HIGH PRESSURE MOVES INTO THE REGION FOR THE WEEKEND AND PROVIDES DRY AND SUNNY WEATHER WITH MODERATING TEMPERATURES.
On Sunday a strong cold front will usher in very windy conditions, cooler temperatures, along with valley rain and mountain snow.
SOUTHERLY WINDS AND A WARMER AIRMASS MOVING IN WILL BOOST TEMPERATURES INTO THE LOWER 50S ACROSS MUCH OF THE FORECAST AREA. AN UPPER LEVEL RIDGE BUILDS ACROSS THE UPPER MISSISSIPPI RIVER VALLEY TONIGHT PROVIDING MOSTLY CLEAR SKIES. SUNDAY WILL BE A VERY PLEASANT DAY ACROSS THE REGION AS THE UPPER RIDGE AMPLIFIES SLIGHTLY ACROSS THE REGION AS A TROUGH DIGS INTO THE SOUTHWEST CONUS. A BROAD TROUGH WILL BE IN PLACE ACROSS THE WESTERN CONUS BY LATE SUNDAY NIGHT.
TODAY-SUN: AN UPPER-DECK TROF THAT HAS BEEN APPROACHING THE PACIFIC NW DURING THE NIGHT IS STILL EXPECTED TO STRENGTHEN. THE SHARPENING TROF SHOULD REACH THE PACIFIC COAST EARLY SUN MORNING. ENABLING A DOWN STREAM NEGATIVELY-TILTED UPPER RIDGE TO AMPLIFY FROM THE MID MS VALLEY TO ALBERTA/SASKATCHEWAN/MANITOBA. THE UPPER PATTERN CHANGES SLOWLY TO A SW REGIME & WITH WESTERN PLAINS TROFFING BECOMING MORE ASSERTIVE. UPPER TROF WILL UNDERGO RAPID CYCLOGENESIS AS IT MOVES E/SE ACROSS AZ & NM ON MON AS IT ENCOUNTERS AN UPPER RIDGE THAT'LL SHARPLY AMPLIFY FROM THE APPALACHIANS TO HUDSON BAY. THE MID-UPPER CYCLONE WILL BE POWERFUL AS IT CONTINUES TO MOVE E TOWARD THE TX/OK PANHANDLES. WITH SUCH A POWERFUL CYCLONE APPROACHING. TUE-WED NIGHT: WITH THE ULTRA-HIGH AMPLTIUDE MID-UPPER RIDGE MOVING VERY SLOWLY E TOWARD THE EAST COAST THE POWERFUL CYCLONE WOULD LIKEWISE BE VERY SLOW-MOVING.
But with clear skies and light winds, temperatures will still dip down into the low to mid 30s most locations, a bit below MOS guidance.
Slowly returning southerly winds will keep tonight's temperatures in the lower to middle 40s. Models begin to spread showers and isolated storms over the region late Sunday evening as a vigorous trough digs across the western states.
1235 AM EST SAT NOV 14 2015 UPPER LEVEL TROUGH DRIVES COLDER AIR INTO THE AREA OVERNIGHT.
346 AM EST SAT NOV 14 2015 HIGH PRESSURE OVER THE TENNESSEE VALLEY TODAY WILL MOVE EAST ACROSS THE MID ATLANTIC REGION TONIGHT AND SUNDAY.
/ISSUED 814 PM CST FRI NOV 13 2015/ HIGH PRESSURE CONTINUES OVER THE AREA. AND THE UPPER LOW PRESSURE TROUGH MOVED EAST.
The sunny skies and drier dwpts will make for ideal conditions for a large temp swing from morning lows in the upper 20s, rising to the lower to middle 60s by this afternoon. Southerly winds around 15 mph will also help to bring in the warmer air.
Could have some MVFR ceilings by late afternoon, but the better chance for the lower ceilings should hold off until later in the evening.
THE HIGH WIND WARNING CONTINUES UNTIL 11PM BUT WINDS ALONG THE ROCKY MOUNTAIN FRONT HAVE BEEN DECREASING DURING THE PAST COUPLE OF HOURS. IF THIS TREND CONTINUES, THE HIGH WIND WARNING MAY END EARLY. THE PERIOD BEGINS WITH A LONGWAVE TROUGH OVER THE NORTHWESTERN US. THE TROUGH FRACTURES WITH AN ALBERTA CLIPPER FORMING IN THE NORTH WHILE THE SOUTHERN PORTION DIGS ACROSS THE GREAT BASIN.
High pressure at the surface was centered over Arkansas early this afternoon with light to moderate southwest winds dominating locally. A sunny sky and relative warm and dry day has resulted with 20Z temps in the lower to middle 60s. The ridge to the east moves little and an intensifying lee trough brings stronger southwest winds and slightly warmer afternoon temps. Erring on the dry side with gusty southwest winds brings the fire danger index into the Very High for much of the area and only slightly warmer/drier/windier conditions could approach Red Flag. An upper level trough is expected to move across the eastern Pacific Saturday night then move onto the west coast on Sunday. Highs Sunday should top out in the lower 60s.
AS COOLER AIR CONTINUES TO FILTER INTO THE REGION FROM THE NW. TEMPS ARE XPCTED TO FALL BELOW 40F AFTER MIDNIGHT AND CONTINUE TOWARD THE FREEZING MARK EARLY SAT MORNING. WITH A STRONG AREA OF HIGH PRESSURE SETTLING INTO THE AREA FROM THE W.
248 AM EST SAT NOV 14 2015 LOW PRESSURE WILL REMAIN OVER THE MARITIMES TODAY AS HIGH PRESSURE BUILDS TOWARD THE EAST COAST.
A VERY PLEASANT WEEKEND IS IN STORE FOR THE AREA AS HIGH PRESSURE BUILDS INTO THE SOUTHEAST BEHIND A COLD FRONT CURRENTLY OVER SOUTH FLORIDA. WITH LOWS EXPECTED TO BOTTOM OUT IN THE UPPER 40S AROUND THE NATURE COAST TO THE LOWER TO MID 60S ACROSS CENTRAL LOCATIONS AND TO THE UPPER 60S OVER SOUTHWEST FLORIDA. THE BOUNDARY WILL STALL OVER SOUTH FLORIDA WITH THE AREA OF HIGH PRESSURE OVER THE SOUTHEAST LEADING TO A TIGHTENING PRESSURE GRADIENT AND A RATHER BREEZY DAY. THE AREA OF HIGH PRESSURE WILL SHIFT FARTHER EASTWARD TO A POSITION OVER THE EAST COAST.
TODAY THROUGH SUNDAY NIGHT MASSIVE NE PAC UPPER TROUGH WILL SPLIT AND DIG SE INTO THE WESTERN CONUS. THIS WILL SUPPORT BROAD UPPER LEVEL RIDGING AND ASSOCIATED WAA INTO THE NORTHERN PLAINS IN THE PERIOD. LONGWAVE UPPER TROUGH WILL SHIFT EAST WITH A POTENT DIGGING SOUTHERN PERIPHERY UPPER TROUGH SUNDAY. THIS WILL SHIFT A LEE SIDE TROUGH EAST SUNDAY NIGHT AS A COLD FRONT.
THE UPPER RIDGE WILL BE AMPLIFYING OVER THE PLAINS STATES. SOME OF THE MODELS ARE HINTING AT A BACKDOOR COLD FRONT DROPPING TO NEAR THE INTERNATIONAL BORDER.
1212 AM EST SAT NOV 14 2015 THIS AFTERNOON WILL FEATURE WINDY AND COLD CONDITIONS WITH HIGHS ONLY INTO THE LOW TO MID 40S. FAIR WEATHER AND MODERATING TEMPERATURES CAN THEN BE EXPECTED THIS WEEKEND AS HIGH PRESSURE BUILDS IN WITH MUCH WARMER TEMPERATURES EXPECTED BY SUNDAY. A TRAILING/SECONDARY TROUGH AXIS AND COLD POOL ALOFT (-30C AT 500 MB) IN THE PROCESS OF PIVOTING THROUGH THE AREA LATE THIS AFTERNOON. SKIES WILL QUICKLY BECOME SUNNY GIVEN BACKING FLOW AND BUILDING ANTICYCLONIC FLOW IN THE LOW LEVELS.
THE FIRST SYSTEM WILL BRING A THREAT OF SHOWERS AND COOLER TEMPERATURES SUNDAY.
DEEP TROUGH SLIDES ONSHORE SUNDAY AS UPPER RIDGE PUSHES EAST.
A WARM LAYER AT 925 MB IS OVER THE WESTERN RIDGE OF THE RED RIVER VALLEY IN ERN ND AND THIS IS SHOWING UP WITH TEMPS WITH LOW TO MID 40S ALONG THE HIGHER TERRAIN FROM WALHALLA TO WESTERN GRAND FORKS COUNTY. AND A BIT COOLER AREA FROM LANGDON ND INTO NW MN.
138 AM EST SAT NOV 14 2015 HIGH PRESSURE MOVING INTO THE TENNESSEE RIVER VALLEY EARLY THIS MORNING WILL BE CENTERED NEAR THE FORECAST AREA SATURDAY NIGHT AND SUNDAY.
108 AM EST SAT NOV 14 2015 RIBBON OF MOISTURE AND INSTABILITY RIGHT ALONG THE EAST COAST, NEAR THE SLOW MOVING COLD FRONT, WILL KEEP MOST SHOWERS AND STORMS JUST OFFSHORE BUT PERSISTENT THROUGH THE NIGHT.
WARMER AIR WILL OVERSPREAD THE FAR WEST LATE THIS MORNING AND CONTINUE ITS ARDUOUS TREK NORTHEASTWARD THROUGHOUT THE AFTERNOON. HIGH PRESSURE AND MODERATING TEMPERATURES WILL BE THE THEME FOR THE SHORT TERM.
A COLD FRONT WILL DROP SOUTHEAST INTO CENTRAL INDIANA TONIGHT. A WAVE OF LOW PRESSURE WILL RIPPLE NORTHEAST ALONG THE FRONT AND NEAR THE INTERSTATE 70 CORRIDOR OVERNIGHT. THE WAVE OF LOW PRESSURE ALONG WITH AN UNSTABLE AND VERY MOIST ATMOSPHERE WILL RESULT IN WIDESPREAD SHOWERS AND THUNDERSTORMS TONIGHT. THE SHOWERS WILL BE ENDING FROM SOUTHWEST TO NORTHEAST ON SUNDAY AND WILL BE REPLACED WITH DRY AND MUCH COOLER WEATHER UNDER THE INFLUENCE OF HIGH PRESSURE.
THIS CONVECTIVE ACTIVITY IS ASSOCIATED WITH A QUICK-MOVING TROF TRACKING ALONG THE US/CAN BORDER THAT IS STEADILY PUSHING INTO NORTHEAST MT. DRIER AIR AND WEAK HIGH PRESSURE WILL MOVE IN TO OUR REGION BEHIND THE PRECIPITATION AS THE TROF DEPARTS.
VISIBLE SATELLITE AND SURFACE OBSERVATIONS SHOWING STRATUS/ STRATOCUMULUS CLOUD COVER ENTRENCHED ACROSS IN THE WAKE OF DEPARTING LOW PRESSURE/COLD FRONT ACROSS THE GREAT LAKES INTO CENTRAL IL. CANADIAN HIGH PRESSURE WAS CLEARING SKIES ACROSS MN INTO FAR NORTHWEST WISCONSIN. PLAN ON A CHILLY NIGHT WITH LOWS IN THE MIDDLE 30S TO THE LOWER 40S. DRY/COOL CONDITIONS PREVAIL THROUGH SUNDAY/SUNDAY NIGHT AS CORE OF THE HIGH ANCHORS ITSELF ACROSS LAKE SUPERIOR/SOUTHERN ONTARIO. LOOK FOR HIGH TEMPERATURES SUNDAY IN THE LOWER/MIDDLE 60S WITH LOWS SUNDAY NIGHT IN THE UPPER 30S TO THE MIDDLE 40S.
THIS EVENING THROUGH SUNDAY NIGHT CURRENT SURFACE MAP PLACES HIGH PRESSURE RIDGE ACROSS THE EASTERN DAKOTAS. WITH TROF ACROSS MONTANA. UPPER LEVEL RIDGE BUILDS ACROSS THE NORTHERN ROCKIES INTO THE HIGH PLAINS. WILL STILL BE AROUND 10F WARMER THAN TODAY.
719 PM CDT SAT MAY 30 2015 SHOWERS AND THUNDERSTORMS GRADUALLY DISSIPATING EARLY THIS EVENING WITH UPPER-TROUGH LINGERING ACROSS THE REGION.
A Canadian frontal system had shifted across southern Missouri this morning, bringing cooler temperatures, cloud cover, and northwest winds. For tonight, expect the potential for some patchy fog development as the cooler air nudges dew points closely. The GFS is suggesting the development of a cluster or rain to develop in this area due to an upper trough axis moving through.
THETA-E AXIS WILL SHARPEN BY MIDDAY FROM N-S ROUGHLY ALONG I-27 AS LEE TROUGHING IN EASTERN NM SPURS A DIFFUSE DRYLINE STRUCTURE. PERSISTENT 700MB RIDGING DIRECTLY OVER THE CWA AND WARMING TEMPS/SUBSIDENCE DO NOT APPEAR FAVORABLE FOR POPS AT THIS TIME. EXCEPTION TO THIS MAY OCCUR JUST AFTER THIS FORECAST WINDOW AS OROGRAPHICALLY-FORCED STORMS IN NM AND SOUTHEAST CO SPREAD S-SEWD DOWNSTREAM OF THE 500-300MB RIDGE AXIS. NORTHERLY FLOW IS EXPECTED TO BE IN PLACE BY SUNDAY EVENING AS UPPER LEVEL RIDGING APPROACHES FROM THE WEST AND AN UPPER LEVEL HIGH DEVELOPS FROM SWRN NM INTO MEXICO. WE MAY SEE SOME TSTM ACTIVITY DEVELOP ACROSS THE HIGHER TERRAIN OF NEW MEXICO AND MAY APPROACH OUR WESTERN ZONES JUST ABOUT ANY DAY. ACTIVITY SHOULD REMAIN RATHER ISOLATED AND HAVE KEEP POPS ON THE LOW END GIVEN THIS EXPECTATION.
HOWEVER, BELIEVE AIR MASS EAST OF COLD FRONT NEAR THE MISSISSIPPI RIVER WILL BE SUFFICIENTLY MOIST AND UNSTABLE TO WARRANT AT LEAST A CHANCE POP FOR TONIGHT.
A NORTH TO NORTHEAST BREEZE GUSTED AROUND 30 MPH AS COOLER AND DRIER AIR BEGAN TO OVERSPREAD EASTERN IOWA AND NORTHERN ILLINOIS. TEMPERATURES AT 3 PM CDT RANGED FROM THE MID 50S ALONG THE HIGHWAY 20 CORRIDOR.
THE LATEST WATER VAPOR IMAGERY DEPICTS SEVERAL IMPULSES ACROSS THE LOWER MISSISSIPPI VALLEY AND SOUTHERN PLAINS INTO THE TENNESSEE VALLEY. CROSSOVER TEMPS THIS AFTERNOON WERE INTO THE LOW 60S AND DO NOT EXPECT WIDESPREAD FOG OVERNIGHT.
A WEAK COLD FRONT WILL MOVE SOUTH INTO DEEP SOUTH TEXAS LATE TONIGHT INTO SUNDAY. A WEAK COLD FRONT IS LOCATED ACROSS CENTRAL TEXAS THIS AFTERNOON. THE WEAK COLD FRONT ACROSS CENTRAL TEXAS WILL DRIFT SOUTH TONIGHT COMBINED WITH SOME UPPER LEVEL SUPPORT WILL MAINTAIN A CHANCE OF SHOWERS AND THUNDERSTORMS TONIGHT. THE REMNANTS OF THE WEAK COLD FRONT WILL PUSH OUT INTO THE NORTHWEST GULF ON THE EAST AND WILL CONTINUE TO SUPPORT CONVECTION UPSTREAM OVER THE RIO GRANDE PLAINS. LOW TEMPERATURES WILL BE IN THE LOWER TO MID 70S TONIGHT WITH LIGHT ONSHORE WINDS. BROAD HIGH PRESSURE ACROSS THE NORTHERN GULF WILL RESULT IN A WEAK PRESSURE GRADIENT ALONG THE LOWER TEXAS COAST. A WEAK COLD FRONT WILL MOVE INTO THE LOWER TEXAS COASTAL WATERS LATE TONIGHT INTO SUNDAY.
IS LOOKING INTERESTING AS A POTENT UPPER LEVEL TROUGH APPROACHES THE AREA.
1235 AM EDT SUN MAY 31 2015 WARM AND HUMID CONDITIONS WILL CONTINUE UNTIL THE PASSAGE OF A STRONG COLD FRONT LATE SUNDAY. COOLER WEATHER WILL SETTLE OVER THE REGION TO START THE WORK WEEK. CONVECTION CONTINUES TO TRAIN ALONG AND JUST SOUTH OF A FRONT THAT GENERALLY EXTENDS DOWN THE LAKE ERIE SHORE LINE BACK TOWARD A LOW IN THE LOWER OHIO VALLEY. THIS LOW WILL EVER-SO-SLOWLY TRACK TOWARD WESTERN PENNSYLVANIA. FRIES MODELS HAVE SLOWED THE COLD FRONTAL PASSAGE LATE SUNDAY.
1145 PM CDT Sat May 30 2015 A Canadian frontal system had shifted across southern Missouri this morning, bringing cooler temperatures, cloud cover, and northwest winds. For tonight, expect the potential for some patchy fog development as the cooler air nudges dew points closely. The GFS is suggesting the development of a cluster or rain to develop in this area due to an upper trough axis moving through.
THERE IS PLENTY OF MOISTURE IN THE LOWER AND MIDDLE PART OF THE ATMOSPHERE THIS EVENING. HEAVY RAIN SUPPORTIVE K INDEX VALUES IN THE LOW 30S ALSO ARE PRESENT. THERE IS A WEAK UPPER LEVEL TROUGH OVER LA AND MS THIS AFTERNOON. THE UPPER LEVEL TROUGH WILL GRADUALLY STRENGTHEN AND ACT AS A FOCUS FOR MORE NUMEROUS THUNDERSTORMS. PART OF THE UPPER LEVEL TROUGH COULD GET CUT OFF AND LINGER OVER LA.
645 PM CDT SAT MAY 30 2015 VISIBLE SATELLITE AND SURFACE OBSERVATIONS SHOWING STRATUS/ STRATOCUMULUS CLOUD COVER ENTRENCHED ACROSS IN THE WAKE OF DEPARTING LOW PRESSURE/COLD FRONT ACROSS THE GREAT LAKES INTO CENTRAL IL. CANADIAN HIGH PRESSURE WAS CLEARING SKIES ACROSS MN INTO FAR NORTHWEST WISCONSIN. PLAN ON A CHILLY NIGHT WITH LOWS IN THE MIDDLE 30S TO THE LOWER 40S. DRY/COOL CONDITIONS PREVAIL THROUGH SUNDAY/SUNDAY NIGHT AS CORE OF THE HIGH ANCHORS ITSELF ACROSS LAKE SUPERIOR/SOUTHERN ONTARIO. LOOK FOR HIGH TEMPERATURES SUNDAY IN THE LOWER/MIDDLE 60S WITH LOWS SUNDAY NIGHT IN THE UPPER 30S TO THE MIDDLE 40S.
AN UPPER RIDGE WILL BUILD INTO THE FORECAST AREA ON SUNDAY. EVEN WITH THIS RIDGE THE AIRMASS WILL BECOME UNSTABLE ENOUGH FOR SCATTERED SHOWERS AND THUNDERSTORMS MAINLY OVER THE MOUNTAINS.
SOME MODELS ALSO HINTING AT LOW LEVEL CLOUDS WORKING BACK INTO NORTHWEST IOWA AS TRAJECTORY BECOMES EASTERLY AND DRAWS ON THE HIGHER MOISTURE STILL IN PLACE ACROSS NORTHERN IOWA. NOT CONVINCED THE HIGH RELATIVE HUMIDITY LEVELS SEEN IN THE MODELS ARE NOT JUST A REFLECTION OF THE COOL AIR MASS MOVING ACROSS THE REGION. ANTICIPATE LOWS ON THE COOLER END OF THE GUIDANCE SPECTRUM WITH READINGS MOSTLY IN THE LOWER 40S. WILL KEEP HIGHS ON THE COOLER SIDE MOST AREAS. WITH CLOUDS AND A MODERATE SOUTHEASTERLY WIND IT WILL BE A MILDER NIGHT WITH LOWS IN THE LOWER TO MID 50S.
LACK OF MUCH LARGE SCALE FORCING AND WEAK STEERING CURRENTS SUGGEST MOST PRECIP WILL REMAIN OVER THE HIGHER TERRAIN WITH ONLY AN ISOLATED STORM OR TWO SURVIVING TO REACH THE INTERIOR VALLEYS AND I- 25 CORRIDOR.
EXPECT A GRADUAL DOWNWARD TREND IN SHWRS AND TSTMS INTO THE OVERNIGHT HOURS AS A COLD FRONT CONTINUES TO TRACK SLOWLY ACROSS THE AREA. COLD FRONT AS OF 18Z WAS ANALYZED FROM NW AR INTO SOUTHERN OK/N CENTRAL TX AND THIS FEATURE SHOULD MAKE GOOD PROGRESS INTO SW AR/NW LA AND NE TX OVERNIGHT. MAIN UPPER TROUGH AXIS SHOULD EXTEND FROM THE GREAT LAKES REGION INTO THE SOUTHERN PLAINS LATE TONIGHT. THIS TROUGH AXIS WILL HELP TO FOCUS ADDITIONAL SHOWER AND THUNDERSTORM ACTIVITY ON SUNDAY BUT COVERAGE SHOULD BE MOSTLY SCATTERED IN NATURE AND MORE FOCUSED ALONG AND TO THE EAST OF THE REMNANT COLD FRONT WHICH MAY STALL LATE TNGT/SUN ACROSS OUR SE ZONES.
626 PM CDT SAT MAY 30 2015 COOL DRY AIR REMAINS IN PLACE WITH A HIGH PRESSURE RIDGE OVERHEAD. THE RIDGE WILL SLOWLY SHIFT EAST TONIGHT. THE HIGHEST POPS REMAIN OVER THE NORTHWEST CWA.
930 PM PDT SAT MAY 30 2015 THE HIGH PRESSURE RIDGE WILL MOVE EAST OUT OF THE REGION SUNDAY AS A LOW PRESSURE TROUGH MOVES INTO THE WEST COAST. THE TROUGH WILL CONTINUE MOST OF THE COMING WEEK.
TEMPS HAVE BEEN SLOW TO RISE TODAY WITH MUCH OF THE AREA STILL IN THE LOW 50S. GUIDANCE TEMPS IN THIS AREA SHOW THE POTENTIAL FOR SOME AREAS TO DIP INTO THE LOWER 30S.
A RIDGE WILL CONTINUE BUILDING OVER THE AREA TONIGHT BRINGING DRIER AND WARMER AIR. THE RIDGETOP CUMULUS AND ISOLATED SHOWERS WILL DISSIPATE AT SUNSET AND ONLY A THIN LAYER OF CIRRUS WILL SPREAD ACROSS THE AREA OVERNIGHT. TEMPERATURES WILL BEGIN TO WARM NICELY UNDER THE RIDGE WITH HIGHS PUSHING TO ABOVE NORMAL TO END OUT MAY.
1000 PM EDT SAT MAY 30 2015 SPRAWLING BERMUDA HIGH PRESSURE WILL EXTEND OVER THE REGION FROM THE EAST THROUGH THE WEEKEND.
BOUNDARY WILL CONTINUE TO PULL SOUTH OF IOWA WITH DECREASING CLOUDS THROUGHOUT THE LATE AFTERNOON AND EVENING AS HIGH PRESSURE WORKS IN ACROSS THE NORTH. THOUGH SLIGHTLY COOLER IN THE NORTH WHERE CLOUDS HAVE HUNG AROUND THROUGHOUT THE DAY KEEPING HIGHS DOWN. THOUGH WARMER IN THE SOUTH WHERE EXPECT SOME CLOUDS TO PERSIST THROUGH MUCH OF THE NIGHT HELPING TO KEEP TEMPERATURES UP SLIGHTLY. BROAD CYCLONIC FLOW ALONG THE ROCKIES AND HIGH PRESSURE OVER THE NERN US WILL ACT TO KEEP IOWA IN GENERAL SE/ERLY FLOW AND A RELATIVELY QUIET WEATHER PATTERN FOR MUCH OF THIS WEEK. +1 TO +2 STD DEV HIGH PRESSURE WILL BE ON THE CANADIAN SIDE OF THE GREAT LAKES. THERE IS A LOT OF DRY AIR IN THE LOW LEVELS TO CONTEND WITH AS SFC DWPT DEPRESSIONS ARE A SOLID 20F.
THE CLOUDS ASSOCIATED WITH THIS WAVE WILL TAKE A BIT LONGER TO EXIT TO THE EAST AS RIDGING EDGES ITS WAY SOUTHWARD DURING THE EVENING HOURS. FURTHER SOUTH AND EAST THE PROBABILITY FOR FROST IS A BIT MORE TENUOUS AS ANOTHER WAVE TRACKING ALONG THE FRONT INCREASES THE PRESSURE GRADIENT WITH THE HIGH BUILDING IN FROM THE NORTH.
1046 PM EDT SAT MAY 30 2015 WARM AND HUMID CONDITIONS WILL CONTINUE UNTIL THE PASSAGE OF A STRONG COLD FRONT LATE SUNDAY. COOLER WEATHER WILL SETTLE OVER THE REGION TO START THE WORK WEEK. AT 8PM COLD FRONT WAS ANALYZED ALONG THE LAKE ERIE SHORELINE. BUT SCATTERED SHOWERS CONTINUE ACROSS THE RIDGES AND NUMEROUS SHOWERS AND THUNDERSTORMS REMAIN JUST NORTHWEST OF THE FORECAST AREA ACROSS NORTHERN OHIO AND NORTHWEST PENNSYLVANIA. THE ONLY EXCEPTION WOULD BE IN THE HIGHER TERRAIN WITH OROGRAPHIC ENHANCEMENT. MODELS HAVE SLOWED THE COLD FRONTAL PASSAGE LATE SUNDAY.
TEMPS WERE IN THE UPPER 70S WITH DEW PTS IN THE LOWER 70S. MSLP PRESSURE PATTERN INDICATED ANOTHER LOW LEVEL COASTAL TROUGH FORMING AND AS THE NIGHT PROGRESSES SHORT RANGE MODEL GUIDANCE INCLUDING THE NMM/ARW/HRRR/SREF ADVERTISED SPOTTY SHOWERS NEARING THE ATLANTIC COAST BUT WITH LESS COVERAGE COMPARED TO WHAT WAS OBSERVED THIS MORNING AS THE TROUGH BEGINS TO BREAK DOWN WHILE RETROGRADING.
UPPER LEVEL TROUGH AXIS CONTINUES TO DIG INTO TEXAS ACROSS W C TX WITH LARGE SCALE ASCENT SPREADING OVER MUCH OF C AND E TX. COLD FRONT HAS PUSHED INTO THE AREA NOW STRETCHING FROM LUFKIN TO BRENHAM.
COOL DRY AIR REMAINS IN PLACE WITH A HIGH PRESSURE RIDGE OVERHEAD. THE RIDGE WILL SLOWLY SHIFT EAST TONIGHT. THE HIGHEST POPS REMAIN OVER THE NORTHWEST CWA.
THIS WILL BE THE WARMEST DAY SO FAR THIS SEASON FOR MANY LOCATIONS WITH MANY OF THE LOWER ELEVATIONS TAKING A RUN AT 80 DEGREES. SUNDAY NIGHT THROUGH SATURDAY THE HIGH PRESSURE RIDGE ALOFT OVER WYOMING WILL BEGIN TO SHIFT EAST AS A PACIFIC LOW PRESSURE TROUGH MOVES INTO THE WEST COAST WITH INCREASING SOUTHWEST FLOW ALOFT. THIS WILL BRING IN WARMER AND DRIER AIR INTO THE SOUTHWEST.
616 PM CDT Sat May 30 2015 A surface cold front has pushed through the forecast area, with cooler and drier air advecting into the region. While a few pockets of drizzle will be possible through tonight as the upper trough axis passes through, the large majority of the area will remain dry, with all measurable precipitation to the east of the forecast area. Temperatures on Sunday will be several degrees warmer than today, with highs in the middle 60s to lower 70s. Overnight lows Sunday night will once again be cool with the dry airmass, clear skies, and light easterly winds, with readings in the lower 50s.
CHATTANOOGA AIRPORT, TN 67 84 65 82 / 20 60 50 50 KNOXVILLE MCGHEE TYSON AIRPORT, TN 67 84 64 81 / 10 50 50 60 OAK RIDGE, TN 67 85 64 81 / 10 50 50 60 TRI CITIES AIRPORT, TN 62 85 62 79 / 10 50 50 60.
RIDGING ALOFT HAS BECOME FIRMLY ESTABLISHED OVER THE SWRN CONUS THIS EVENING WITH 00Z RAOB DATA INDICATING H5 589DM HEIGHTS CENTERED DIRECTLY OVER ARIZONA. /330 PM MST SAT MAY 30 2015/ REGIONAL UPPER AIR PLOTS/SATELLITE IMAGERY REVEAL THE UPPER LEVEL RIDGE OVER THE SOUTHWESTERN STATES. THE AXIS OF 585-587DM HEIGHTS STRETCHED OVER SOUTHERN CALIFORNIA CLOSE TO THE LOWER COLORADO RIVER VALLEY AND PROGGED TO SHIFT GRADUALLY EAST WITH TIME.
Later this evening the low passes to our north and we'll see showers dissipate west to east. Wrap around clouds are expected to begin to push in overnight, along with slightly cooler air. This should keep highs in the upper 60s to 70s, especially across southern IN and northern KY, notably cooler compared to recent days.
ALSO ADJUSTED THE HOURLY TEMPS DOWNWARD FOR THIS EVENING AND LOWERED THE OVERNIGHT MINS IN SOME LOCATIONS TO ACCOUNT FOR THE COOLER TEMPS THIS EVENING. AHEAD OF A SURFACE FRONT CONTINUING TO ROTATE AROUND A BROAD TROUGH SLOWLY ADVANCING EAST TOWARD THE LOWER MISSISSIPPI RIVER VALLEY.
BETWEEN THE CLOUDS AND THE MOIST GROUND THIS WILL TAKE A COUPLE DEGREES OFF THE HIGHS.
THIS HIGH POP REGIME WILL CONTINUE INTO THE EVENING HOURS UPPER LOW OPENS OUT ON ITS MOVE ACROSS MID MISSISSIPPI AND LOWER OHIO RIVER VALLEYS AND DRIVES COLD FRONT THRU FOR PASSAGE. ANOTHER LOBE OF ENERGY DOES LIFT ACROSS MEAN UPPER TROF AND THRU OUR AREA TMRW.
1004 PM EDT SAT MAY 30 2015 WARM AND HUMID CONDITIONS WILL CONTINUE UNTIL THE PASSAGE OF A STRONG COLD FRONT LATE SUNDAY. COOLER WEATHER WILL SETTLE OVER THE REGION TO START THE WORK WEEK. AT 8PM COLD FRONT WAS ANALYZED ALONG THE LAKE ERIE SHORELINE. BUT SCATTERED SHOWERS CONTINUE ACROSS THE RIDGES AND NUMEROUS SHOWERS AND THUNDERSTORMS REMAIN JUST NORTHWEST OF THE FORECAST AREA ACROSS NORTHERN OHIO AND NORTHWEST PENNSYLVANIA. THE ONLY EXCEPTION WOULD BE IN THE HIGHER TERRAIN WITH OROGRAPHIC ENHANCEMENT. MODELS HAVE SLOWED THE COLD FRONTAL PASSAGE LATE SUNDAY.
RESULTING IN A DEEPER MARINE LAYER AND COOLER TEMPERATURES ON SUNDAY.
WITH DRIER AIR IN PLACE, A COOLER OVERNIGHT IS FORECAST THAN HAS BEEN SEEN IN PAST COUPLE OF WEEKS. THE NAM AND RAP13 ARE BOTH FAVORABLE FOR RADIATION FOG AFTER 9 UTC, HOWEVER THE RAP 13 DOES NOT EXTEND ANY FARTHER WEST THAN CENTRAL KANSAS VERY PATCHY COVERAGE, WHILE THE NAM , WHICH IS OFTEN TOO AGGRESSIVE, EXTENDS AREAS OF FOG MUCH FARTHER WEST INTO THE HIGHWAY 83 CORRIDOR. WOULD LIKE TO SEE SOME BETTER SUPPORT FROM THE LOCAL GFS MOS, BUT MAY ADD SOME PATCHY FOG MENTION TO THE WX GRIDS IN THE LOWER SURFACE DEWPOINT DEPRESSION AXIS ACROSS OUR NORTH CENTRAL COUNTIES EARLY SUNDAY. THE NAM AND THE GFS ARE QUITE DIFFERENT WITH RESPECT TO THE MAGNITUDE OF THE MOISTURE RETURN ACROSS THE HIGHWAY 83-COLORADO BORDER CORRIDOR SUNDAY/SUNDAY EVENING.
/ISSUED 307 PM CDT Sat May 30 2015/ The cold front has made its way to the Rio Grand leaving cooler temperatures in its wake. We will get a break from the wet pattern we have been under with an upper ridge that will move east over the area.
WATER VAPOR IMAGERY SHOWING AN UPPER LOW OVER BRITISH COLUMBIA. THIS LOW WILL EJECT A FEW DISTURBANCES ACROSS OUR FORECAST AREA THIS AFTERNOON/EVENING AND AGAIN ON SUNDAY AS IT SLOWLY MOVES EAST ACROSS SOUTHERN CANADA.
THE WESTERN FLANK OF A RIDGE (CENTERED OVER THE WESTERN ATLANTIC) CURRENTLY RETREATING FROM THE SOUTHEAST IS ACTUALLY PREVENTING A FURTHER SPREAD EASTWARD IN THUNDERSTORM DEVELOPMENT. THIS IS WHERE THE FORECAST IS RATHER CHALLENGING IN TERMS OF THUNDERSTORM CHANCES AS DIFF VORTICITY ADVECTION FROM THE SOUTHERN FLANK OF THE SHEARED TROUGH IS SHOWN BY SOME MODEL RUNS CLOSING OFF OVER THE LOWER MS RIVER VALLEY AMPLIFIED RIDGE BUILDS OVER S PLAINS.
THAT WAS ASSOCIATED WITH A 500 MB TROUGH THAT HAD 12 HOUR HEIGHT FALLS OF UP TO 150 METERS. A WEAK TROUGH WAS LOCATED FROM WISCONSIN BACK INTO EASTERN NEBRASKA. A BROAD AND FAIRLY FLAT RIDGE WAS TO OUR WEST. 700 MB TROUGH WAS TO OUR EAST BUT SOME MOISTURE AT THIS LEVEL WAS LINGERING. RIDGE AXIS STRETCHED FROM MANITOBA INTO EASTERN COLORADO.
Persistent stratus cloud deck has been slowly eroding from the northwest today, but it appears unlikely that clouds will not dissipate much east of the Highway 81 corridor by this evening. With the clouds in place, afternoon highs will struggle into the lower 60s. and lows should range from the lower 50s east to the middle 40s in north central KS where more clearing is expected. This will make for a pleasant Sunday afternoon with highs in the lower 70s. Tomorrow night the moisture begins to advect northward over the high plains. During this time the flow aloft remains out of the northwest as the upper ridge builds over the southern Rockies.