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April 2012

04/30/2012

BUMPY RIDE TO A LATE WEEK WARM-UP

IT'S HARD TO BELIEVE THAT THE MONTH OF APRIL IS ALMOST OVER! AS WE TALKED ABOUT LATE LAST WEEK, THE TEMP DEPARTURE FROM APRIL 2012 WILL NOT BE NEARLY AS IMPRESSIVE AS IT WAS LAST MONTH. OVERALL, THIS PAST MONTH HAS BROUGHT MORE TYPICAL UP AND DOWN SWINGS IN TEMPS THAT YOU NORMALLY SEE IN THE SPRING. THAT'S BECAUSE WE WERE FINALLY ABLE TO TAP INTO SOME PRETTY CHILLY AIR MASSES FROM CENTRAL AND EASTERN CANADA.

HEADING INTO THE FIRST SEVERAL DAYS OF MAY, IT APPEARS THAT WE HAVE PLENTY OF TEMP CHALLENGES. EVENTUALLY, IT COULD BECOME QUITE WARM AROUND HERE BY THE END OF THE WEEK. HOWEVER, UNTIL THEN, THE COMBINATION OF MOISTURE (CLOUDINESS) AND AN ONSHORE FLOW WILL LIKELY HAVE A LIMITING EFFECT ON HOW HIGH READINGS ARE ABLE TO GET HERE.

IN THE SHORT TERM, A SURFACE HIGH PRESSURE RIDGE IS MOVING OFF TO OUR EAST. THAT IS ALLOWING THE FLOW TO TURN SOUTHEASTERLY. DEW POINTS ACROSS OUR AREA ARE STILL LOW. HOWEVER, NOT TOO FAR AWAY TO THE SOUTH AND WEST, THEY ARE ON THEIR WAY UP. THIS ZONE INCLUDES THE DELMARVA PENINSULA BACK INTO THE BALTIMORE-WASHINGTON AREA. AT THE LEADING EDGE OF THE HIGHER DEW POINTS, WE ACTUALLY SAW A DECK OF LOW STRATUS CLOUDS ADVANCING NORTHEASTWARD TODAY. THE INITIAL ARM OF WARM ADVECTION CLOUDS AND SHOWERS WILL PROBABLY MISS US TO THE NORTH AND NORTHWEST THIS EVENING. THEN, WE DO EXPECT THINGS TO RELOAD OVERNIGHT AS A NICE LOW LEVEL JET COMBINES WITH WARM ADVECTION TO BRING US A ROUND OF SHOWERS AND EVEN A T-STORM. IT IS POSSIBLE THAT IT JUST RAINS FOR A FEW HOURS LATE TONIGHT INTO TOMORROW MORNING. THAT WILL MEAN A DAMP AND POTENTIALLY WET MORNING RUSH HOUR. AS FOR HOW MUCH RAIN IS GOING TO FALL HERE, WE FEEL THAT THE MOST LIKELY AMOUNT WILL BE 1/4" TO 1/2".

A SURFACE LOW NOW OUT IN THE MIDWEST WILL TRACK TO NEAR ROCHESTER, NY BY 12Z TOMORROW. FROM THERE, THE LOW WILL PROBABLY TURN MORE SOUTHEASTWARD OVER TIME, AS A TRIPLE POINT LOW DEVELOPS. JUST WHERE THAT TRIPLE POINT LOW FORMS AND TRACKS WILL HAVE A MAJOR BEARING ON TEMPS TOMORROW. WE ARE QUITE CONFIDENT THAT FROM EASTERN NY STATE AND INTO MUCH OF NEW ENGLAND, TOMORROW WILL BE A CLOUDY, COOL DAY.  MEANWHILE, FARTHER TO THE WEST AND SOUTHWEST, CLOUDS WILL HAVE A MUCH EASIER TIME BREAKING. THAT COMBINED WITH A WEST OR NORTHWEST SURFACE FLOW WILL LEAD TO A WARM AFTERNOON. THIS IS ESPECIALLY THE CASE ACROSS INTERIOR SOUTHERN NJ, DE, SOUTHEASTER, PA, MD, AND INTO VA. IT IS CONCEIVABLE THAT TOMORROW AFTERNOON, WE ARE DEALING WITH A RANGE IN TEMPS FROM NEAR 80 TO THE MID 50S OVER A DISTANCE OF 100 MILES OR SO.

AFTER TOMORROW'S FEATURE GOES BY, THERE WILL BE A BRIEF PERIOD OF QUIET WEATHER HEADING INTO MID-WEEK. THEN, WE'LL PROBABLY HAVE TO DEAL WITH ADDITION CHANCES OF SHOWERS AND/OR T-STORMS LATER IN THE WEEK AND INTO THE START OF THE WEEKEND AS WARM, HIGHER DEW POINT AIR TRIES TO MAKE A MOVE NORTHEASTWARD. UNTIL THAT HAPPENS, THERE IS A GOOD CHANCE THAT AN ONSHORE FLOW SETUP GIVES US MORE HEADACHES WITH TEMPS HERE ON WEDNESDAY AND THURSDAY. WEDNESDAY IS SOMEWHAT DICEY, AS THE FLOW WILL BE TURNING TO THE SOUTHEAST VIA NORTHEAST AND EAST. IF THERE ARE ENOUGH BREAKS OF SUN THAT DAY, WE HAVE TO BE CAREFUL NOT TO GO TOO COOL. THERE IS A BETTER CHANCE OF TEMPS UNDER-ACHIEVING ON THURSDAY. SOMETHING TO KEEP IN MIND FOR LATER THIS WEEK IS THAT UNTIL WE GET RID OF THE MARINE INFLUENCE, THUNDER IS NOT TOO LIKELY TO OCCUR.

04/23/2012

TEMPS STRUGGLE IN THE WAKE OF SUNDAY SOAKER

HAPPY LAST FULL WEEK OF APRIL! IN LOOKING BACK AT THE PAST SEVERAL DAYS, IT APPEARS THAT OVERALL, THE WEATHER TURNED OUT PRETTY CLOSE TO WHAT WE WERE FORECASTING LATE LAST WEEK. THIS STORM REALLY DID DEEPEN NICELY LAST NIGHT, RESULTING IN HEAVY RAIN AND STRONG WINDS. INCLUDING WHAT FELL ON SATURDAY, THE STORM RAINFALL TOTAL FOR THE PARK WAS 2.89". AS FOR WINDS, A NUMBER OF LOCATIONS ALONG THE COAST REPORTED GUSTS TO OR PAST 50 MPH. LGA AIRPORT HAD A PEAK GUST TO 54 MPH. OF COURSE, THE OTHER MAJOR IMPACT OF THIS STORM WAS THE SNOW ON ITS WEST SIDE. ON THE ALLEGHENY FRONT 5-6" OF WET SNOW PILED UP, AND WE DID HAVE SOME REPORTS OF AS MUCH AS 8" IN PARTS OF SOMERSET COUNTY IN THE LAUREL HIGHLANDS. SOME AREAS NORTH OF HERE DID PRETTY WELL ALSO, PARTICULARLY THE HIGH GROUND FROM TIOGA AND POTTER COUNTY, PA WESTWARD, AND ALSO NORTHWARD SOMEWHAT INTO NY STATE.

THE ACTUAL TRACK OF THE LOW WAS SOMEWHAT FARTHER EAST THAN SOME OF THE MODELS WERE HINTING AT. ACTUALLY, THE TRACK WAS MORE IN LINE WITH CLIMO AND STATISTICS. THE LOW, WHICH IS NOW CLOSE TO BEING OCCLUDED, IS CENTERED BETWEEN ALBANY AND UTICA, NY. THIS SYSTEM WILL CONTINUE TO TRACK NORTHWESTWARD DURING THE NEXT 24-36 HOURS, EVENTUALLY HEADING INTO SOUTHEASTERN ONTARIO AND THEN INTO WESTERN QUEBEC. THE UPPER LEVEL CLOSED LOW, WHICH IS NOW CENTERED OVER WESTERN OR CENTRAL PA, WILL ALSO PUSH NORTHWARD INTO CANADA OVER THE NEXT COUPLE OF DAYS.

BY WEDNESDAY, THIS CLOSED LOW WILL OPEN UP, AND THE TROF WILL PUSH EASTWARD THROUGH THE NORTHEASTERN STATES AND EASTERN CANADA. SO, TO ONE DEGREE OR ANOTHER, WE WILL BE DEALING WITH SOME RESIDUAL EFFECTS OF THIS STORM THROUGH MID-WEEK. THE RESULT WILL BE A GOOD DEAL OF CLOUDINESS TONIGHT AND TOMORROW WITH A PASSING SHOWER HERE AND THERE AND FROM TIME TO TIME. WITH TOMORROW BEING A VERY UNSTABLE DAY, THE MOST LIKELY TIME FOR SCATTERED INSTABILITY SHOWERS TO BE AROUND WOULD BE IN THE AFTERNOON AND EARLY EVENING HOURS. WITH THE INSTABILITY TOMORROW, AND STILL A DECENT PRESSURE GRADIENT, WE DO EXPECT IT TO BE QUITE BRISK, AND PROBABLY DOWNRIGHT WINDY AT TIMES.

THE ATMOSPHERE WILL PROBABLY SETTLE DOWN A BIT TOMORROW NIGHT, BUT THEN WE ARE STILL ALLOWING FOR AT LEAST A STRAY SHOWER ON WEDNESDAY AS THE TROF PULLS EASTWARD. THE FARTHER NORTH AND NORTHEAST YOU GO, THE BETTER THE CHANCE IS THAT THE SHOWER WILL OCCUR. OTHERWISE, WEDNESDAY WILL BE MAINLY DRY WITH MORE CLOUDS THAN SUNSHINE. TEMPS EACH OF THE NEXT TWO DAYS WILL BE CLOSE TO EACH OTHER, MOST LIKELY WITHIN A FEW DEGREES.

LATER IN THE WEEK AND INTO THE UPCOMING WEEKEND, WE HAVE A COUPLE OF CHALLENGES AS TO THE STRENGTH, TIMING, AND TRACK OF ADDITIONAL SYSTEMS. THIS, IF COURSE, WILL HAVE A MAJOR BEARING ON WHAT TEMPS ARE LIKE HERE. IT DOES LOOK LIKE SOME DISTURBANCE WILL COME THROUGH THE REGION ON THURSDAY, AND THEN ANOTHER ONE AT SOME POINT OVER THE WEEKEND(MOST LIKELY SUNDAY). IN BETWEEN, FRIDAY WILL PROBABLY BE A DRY DAY, AND TEMPS THAT DAY LOOK RATHER COOL...IN RELATION TO NORMAL.

04/19/2012

CHALLENGING WEEKEND FORECAST

THE LONG RANGE CONTINUES TO BE FRUSTRATING, AS WE DEAL WITH MORE MODELS DIFFERENCES. FROM SUNDAY INTO EARLY NEXT WEEK, THE 00Z RUN OF THE EURO AND CANADIAN ACTUALLY LOOKED PRETTY SIMILAR. BOTH OF THESE MODELS DEVELOP A LOW ALONG THE FRONTAL BOUNDARY LATE IN THE WEEKEND, IN RESPONSE TO THE DIGGING UPPER LEVEL TROF TO THE WEST. FROM SUNDAY INTO MONDAY, THIS LOW IS FORECAST TO DEEPEN EXPLOSIVELY AS IT TRACKS NORTHWARD AND THEN EVENTUALLY EVEN TURNS MORE NORTHWESTWARD.

THE GFS HAS A SOMEWHAT SIMILAR SOLUTION, ALTHOUGH IT IS MUCH FARTHER TO THE EAST AND NORTHEAST WITH THE TRACK OF THE LOW. THAT IS LIKELY DUE TO THE FACT THAT THERE IS NO PHASING WITH THE DIGGING NORTHERN BRANCH TROF AND THE STRONG SOUTHERN BRANCH SHORT WAVE DOWN IN THE SOUTHEASTERN STATES.

THE NAM HAS A VERY FLAT LOOKING UPPER LEVEL PATTERN BY LATE SUNDAY, WITH NO HINT OF A STORM.

IF YOU TOOK THE LATEST RUN (12Z) OF THE EURO LITERALLY, IT IS FORECASTING A

MAJOR SNOWSTORM BACK IN PARTS OF THE APPALACHIANS, WITH A GOOD RAIN EVENT FARTHER EAST. OF COURSE, WITH ALL OF THE DRY WEATHER OF THE PAST MONTH AND A HALF, AND THE NUMBER OF BRUSH FIRES THAT HAVE OCCURRED, A SOAKING RAIN WOULD CERTAINLY BE A MAJOR BLESSING. ALL OF US, TO SOME DEGREE OR ANOTHER, ARE ROOTING FOR A MAJOR RAIN HERE. HOWEVER, GIVEN ALL OF THE FLIPPING AND FLOPPING THAT WE'VE SEEN WITH THE MODELS FROM DAY TO DAY AND RUN TO RUN, WE ARE JUST NOT READY TO ANY BANDWAGON IN ONE DIRECTION OR ANOTHER. THE HOPE IS THAT WE END UP WITH AT LEAST ENOUGH RAIN TO ALLEVIATE THE FIRE DANGER, AND MAYBE WE GET SOME BONUS BEYOND THAT.

IF THIS BIG STORM SCENARIO COMES TO FRUITION, IT IS LIKELY TO BE IN THE LATE SUNDAY, SUNDAY NIGHT, AND MONDAY TIME FRAME.

BEFORE THEN, THE TREND FOR AWHILE THIS WEEKEND WILL BE FOR THE COLD FRONT TO KEEP PUSHING ALONG AND MAKING SLOW BUT STEADY PROGRESS SOUTHEASTWARD. FOR THAT REASON, WE DO FEEL THAT NORTH AND WEST OF A CERTAIN POINT...PERHAPS FROM THE NORTHERN AND WESTERN SUBURBS OF WASHINGTON AND BALTIMORE UP TO THE POCONOS AND CATSKILLS...SUNDAY WILL END UP BEING A DRY DAY. THAT DRY ZONE COULD EVEN BE SOMEWHAT FARTHER SOUTH AND EAST. BASICALLY, THE CLOSER TO THE COAST YOU GO ON SUNDAY, THE MORE LIKELY IT IS TO STAY CLOUDY, AND ALSO THE MORE LIKELY IT IS TO RAIN AT LEAST A BIT. ANY EXPANSION OF THE RAIN ZONE ON SUNDAY WILL PROBABLY HOLD OFF UNTIL LATE IN THE DAY.

REGARDLESS OF HOW THE SUNDAY NIGHT-MONDAY TIME FRAME PANS OUT, TUESDAY IS LOOKING WINDY AND COOL WITH LOTS OF CHILLY AIR ALOFT. THAT WILL RESULT IN MORE CLOUDS THAN SUN HERE WITH A CONTINUED CHANCE OF INSTABILITY SHOWERS.

IN THE SHORTER TERM, OUR WEATHER LOOKS QUIET TONIGHT AND TOMORROW, AND WE REALLY HAVEN'T CHANGED OUR THINKING ON TEMPS MUCH FROM WHAT WE HAD OUT YESTERDAY. THE SHORE WILL BE COOLER TOMORROW DUE TO A SOUTHERLY OR SOUTH TO SOUTHEAST SURFACE FLOW. AFTER A MILD NIGHT TOMORROW NIGHT, SATURDAY WILL BE ANOTHER WARM DAY. THE ACTUAL HIGH TEMPS ON SATURDAY WILL DEPEND ON THE TIMING OF ANY SHOWERS AND T-STORMS ASSOCIATED WITH THE COLD FRONT ARRIVING FROM THE NORTHWEST. OF COURSE, WITH A SOUTHERLY FLOW AGAIN ON SATURDAY, COASTAL TEMPS WILL BE HELD DOWN.

04/17/2012

SUMMER PREVIEW ENDS TONIGHT

AFTER THE SUMMERLIKE DAY YESTERDAY, TODAY IS STILL PRETTY WARM FOR THE MIDDLE OF APRIL. HOWEVER, AS WE POINTED OUT, THE DEW POINTS ARE MUCH LOWER THAN YESTERDAY, AND SO THE AIR MASS HAS A NOTICEABLY DIFFERENT FEEL. THE TREND TOWARD ADDITIONAL COOLING WILL CONTINUE DURING THE NEXT 24 HOURS, AND TEMPS TOMORROW WILL END UP BEING CLOSER TO NORMAL FOR THIS TIME OF YEAR.

READINGS WILL TREND BACK UPWARD AGAIN LATER THIS WEEK, STARTING ON THURSDAY, AND THEN PEAKING OUT ON FRIDAY OR SATURDAY. AREAS AWAY FROM ANY WATER INFLUENCE WILL LIKELY REACH THEIR MAX TEMPS ON SATURDAY, AHEAD OF THE NEXT COLD FRONT, WHILE COASTAL LOCATIONS WILL END UP BEING FAIRLY SIMILAR BOTH DAYS...DUE TO A MORE SOUTHERLY, ONSHORE FLOW.

TEMPS DURING THIS NEXT WARM SPELL WILL BE NOWHERE NEAR AS HIGH AS WHAT WE JUST EXPERIENCED. DOWN THE ROAD, IT WILL PROBABLY TURN WAY COOLER. PLENTY OF VERY CHILLY AIR WILL BE AVAILABLE TO GET TAPPED BEHIND THE FRONTAL BOUNDARY. THAT WILL LOWER TEMPS DRAMATICALLY AT SOME POINT THIS WEEKEND, AND THEN IT WILL STAY QUITE COOL INTO EARLY NEXT WEEK. IF THAT CHILLY AIR IS COMBINED WITH SOME RAIN, THEN READINGS WILL BE VERY LOW...CERTAINLY LOWER THAN WE NOW HAVE IN OUR FORECAST.

WE DID TRIM SOME TEMPS IN THE LONGER RANGE, BUT WE ARE HESITANT TO GO ALL THE WAY, THIS FAR OUT. THE BIGGEST CHALLENGE THAT WE WILL HAVE HEADING INTO THE WEEKEND IS THE TIMING OF THE COLD FRONT AND ANY SIGNIFICANT PRECIP. WE TEND TO FAVOR THE SLOWER EURO SOLUTION IN THAT REGARD, BUT MORE FINE TUNING IS LIKELY TO OCCUR DURING THE NEXT FEW DAYS.

IN THE SHORTER TERM, TONIGHT WILL REMAIN DRY WITH PATCHY CLOUDINESS AROUND. OVERALL, CLOUDS WILL WIN OUT OVER SUN TOMORROW AS A WAVE FORMS ON THE FRONT NOW TO OUR SOUTH, IN RESPONSE TO A HEALTHY SOUTHERN BRANCH SHORT WAVE THAT WILL PASS BY WELL TO OUR SOUTH. THERE IS STILL SOME DEBATE AS TO NOW FAR NORTH ANY SHOWERS GET THAT WILL BE ASSOCIATED WITH THE SOUTHERN WAVE. IT LOOKS LIKE THERE IS A DECENT SETUP FOR AT LEAST SEVERAL HOURS OF STEADY RAIN FROM PORTIONS OF MD, DE, VA, AND PERHAPS EXTREME SOUTHERN NJ SOUTHWARD. WE DO FEEL THAT AT LEAST A SHOWER OR TWO WILL BE ABLE TO GET FARTHER NORTHWARD INTO PORTIONS OF PA, NJ, THE NYC AREA, AND MAYBE EVEN SOUTHERNMOST NEW ENGLAND.

BY THURSDAY, MOISTURE FROM THIS FEATURE WILL BE EXITING THE SCENE, ALLOWING FOR A RETURN OF SOME SUN. THE WORK WEEK WILL END ON A DRY, PLEASANT NOTE AS HIGH PRESSURE PUSHES OFF THE EAST COAST, WHILE AN UNSETTLED ZONE SETS UP TO OUR NORTH AND NORTHWEST...CLOSER TO THE NEXT FRONTAL BOUNDARY.