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July 2010

07/29/2010

Relief arrives!

THE COOL FRONT CONTINUES TO MAKE SLOW BUT STEADY PROGRESS SOUTHEASTWARD. AS WE SUSPECTED, THE TIMING OF THE FRONTAL BOUNDARY WAS NOT THE MOST FAVORABLE FOR SEVERE WEATHER HERE. THE STRONGEST T-STORMS TODAY OCCURRED ACROSS PARTS OF CENTRAL AND SOUTHERN NJ, DE, MD, AND VA. OF COURSE, THERE IS CURRENTLY A BOX OUT FOR THAT ZONE UNTIL 7 PM.

FARTHER TO THE NORTH, DEW POINTS ARE NOW LOWERING NICELY. AT 2PM, WHILE THE DEW POINT IN THE PARK WAS 70, IT WAS DOWN TO 58 AT SCRANTON AND 56 AT BINGHAMTON. THAT NOTICEABLY MORE COMFORTABLE AIR MASS IS HEADED OUR WAY, AND THAT WILL SET UP A COUPLE OF VERY NICE DAYS HERE WEATHER WISE TOMORROW AND SATURDAY. TOMORROW WILL FEATURE SUNSHINE AND SOME FAIR WEATHER CUMULUS CLOUDS ALONG WITH PLEASANT TEMPS AND LOW HUMIDITY. WITH HIGH PRESSURE SETTLING INTO THE NORTHEAST TOMORROW NIGHT, WE EXPECT CLEAR SKIES, LIGHT WINDS, AND THE COOLEST TEMPS THAT WE HAVE EXPERIENCED SINCE EARLY THIS MONTH.

SATURDAY WILL BE SUNNY TO PARTLY CLOUDY AND COMFORTABLE WITH AFTERNOON READINGS WITHIN A DEGREE OR TWO OF TOMORROW. UNFORTUNATELY, OUR WEATHER WILL DETERIORATE DURING THE SECOND HALF OF THE WEEKEND. AS THE SURFACE HIGH RETREATS TO THE NORTHEAST OFF OF THE NEW ENGLAND COAST, OUR SURFACE FLOW WILL TURN EAST TO SOUTHEASTERLY. AT THE SAME TIME, MOISTURE WILL BE MOVING INTO THE REGION FROM THE WEST IN THE MID AND UPPER LEVELS, AS AN UPPER LEVEL TROF BECOMES ESTABLISHED OVER THE EASTERN PART OF THE COUNTRY. AS A RESULT, WE ARE FORECASTING PLENTY OF CLOUDINESS HERE ON SUNDAY ALONG WITH SOME SHOWERS. THAT COMBINED WITH THE ONSHORE FLOW WILL LEAD TO COOLER TEMPS ON SUNDAY. MANY LOCATIONS WILL END UP NOT GETTING OUT OF THE 70S FOR THE FIRST TIME IN AWHILE. WE ARE CONCERNED THAT A FORECASTOF SHOWERS FOR SUNDAY JUST WON'T CUT IT IN SOME PLACES, AS THERE IS THE POTENTIAL FOR SEVERAL HOURS OF STEADIER RAIN, INCLUDING DOWNPOURS. JUST WHERE THAT WILL HAPPEN, HOWEVER, IS STILL VERY TOUGH TO PINPOINT. OUR GUT FEELING IS THAT IT MAY TEND TO BE FAVORED SOME PARTS OF VA, MD, AND DE UP INTO THE UPSLOPE AREAS OF PA. HOWEVER, WE SHOULD STILL WAIT FOR AT LEAST ANOTHER DAY BEFORE WE GET MORE SPECIFIC WITH THE HEAVY RAIN POTENTIAL.

LOOKING AHEAD, THE TROF WILL BE SLOW TO LIFT OUT ON MONDAY, ALTHOUGH HEIGHTS WILL BE SLOWLY RISING BY THEN. THAT SHOULD LEAD TO LESS ACTIVITY AND SLIGHTLY HIGHER TEMPS. WE WILL LIKELY GET BACK INTO A VERY WARM, HUMID PATTERN AGAIN BY THE MIDDLE OF NEXT WEEK.

07/19/2010

Heat Wave Reaches Day 4

LAST WEEK WE KEPT TALKING ABOUT THE UPCOMING PATTERN THIS WEEK, AND DESCRIBED IT AS A "RIM OF THE RIDGE" PATTERN. THAT PRETTY ACCURATELY DESCRIBES OUR WEATHER HERE FOR MUCH OF THIS WEEK AND INTO THE WEEKEND. THE UPPER LEVEL RIDGE, REPRESENTING THE CENTER OF A VERY HOT AIR MASS, IS NOW CENTERED OUT IN THE SOUTHERN PLAINS STATES. DURING THE NEXT SEVERAL DAYS, THE RIDGE WILL TEND TO ELONGATE SOMEWHAT AND BUILD EASTWARD INTO THE SOUTHEASTERN STATES. HOWEVER, THEHIGH ITSELF WILL NEVER REALLY BUILD INTO THE MID-ATLANTIC OR NORTHEAST STATES...ALTHOUGH WILL RISE A BIT LATE IN THE WEEK AND HEIGHTS WILL PROBABLY PEAK ON FRIDAY INTO THE START OF THE WEEKEND.

IN SETUP LIKE THIS, WE REMAIN IN AN ABOVE NORMAL TEMP PATTERN, BUT WE NEVER REALLY INTO THE CORE OF THE HEAT WHERE TEMPS CAN BE EXCESSIVELY HIGH DAY AFTER DAY. THAT IS NOT TO SAY THAT WE CAN'T GET A BRIEF ONE OR TWO DAY INCURSION OF EXTREME HEAT. THAT CERTAINLY MAY BE THE CASE FOR AREAS SOUTH OF THE MASON-DIXON LINE ON FRIDAY AND SATURDAY, AND PERHAPS ACROSS THE NORTHEAST STATES EAST OF THE APPALACHIANS ON SATURDAY. TEMPS DURING THAT PERIOD COULD EASILY RISE WELL INTO THE 90 IN THE BIG EAST COAST CITIES, AND ANOTHER 100 DEGREE DAY IS NOT OUT OF THE QUESTION. EVEN BACK IN THE MOUNTAINS, THERE IS LIKELY TO BE AT LEAST ONE PRETTY HOT DAY LATE THIS WEEK.

THIS IS THE TIME OF YEAR WHEN WE REALLY CAN'T KEEP DEW POINTS DOWN FOR ANY LENGTH OF TIME. THAT WILL CERTAINLY BE THE CASE THIS WEEK. HOWEVER, THERE WILL BE A COUPLE OF BRIEF PERIODS WHEN HUMIDITY LEVELS DO DROP A BIT...ONE BEING LATE TONIGHT INTO TOMORROW.

THE MOST CHALLENGING ASPECT OF THIS TYPE OF PATTERN IS TRYING TO FIGURE OUT THE TIMING AND INTENSITY OF DISTURBANCES MOVING ALONG IN THE FLOW, EACH OF WHICH COULD KICK OFF SOME SHOWER AND T-STORM ACTIVITY. OBVIOUSLY, FIRST AND FOREMOST IN THE CONCERNS IN THE NOWCAST THIS EVENING, AS WE DEAL WITH SCATTERED, BUT STRONG T-STORMS. ONCE THE FRONTAL BOUNDARY PUSHES EAST OF US, THEN THE ATMOSPHERE WILL SETTLE DOWN TONIGHT. THE QUIET PERIOD WILL LAST INTO TOMORROW. THE NEXT DISTURBANCE SEEMS DESTINED TO CROSS THE REGION LATER TOMORROW AND TOMORROW NIGHT INTO WEDNESDAY.

07/12/2010

Hot start, and finish. Muggy and stormy in the middle.

FROM THE MIDDLE OF JULY WELL INTO AUGUST, IT IS TOUGH TO GET ANY EXTENDED STRETCH OF REALLY COMFORTABLE WEATHER WITH LOW DEW POINTS. IT CERTAINLY DOES HAPPEN FROM TIME TO TIME, MORE SO IN SOME YEARS THAN IN OTHERS. HOWEVER, THE NORM NOW IS A DAY OR TWORELIEF, FOLLOWED BY MORE STICKY CONDITIONS. FOR THE NEXT SIX WEEKS OR SO, THE HUMID OR VERY HUMID DAYS WILL DEFINITELY OUTNUMBER THE PLEASANT DAYS.

WE DID EXPERIENCE A NICE DROP IN DEW POINTS YESTERDAY, AND HUMIDITY LEVELS TODAY STILL AREN'T TOO BAD. HOWEVER, DEW POINTS WILL BE ON THEIR WAY BACK UP AGAIN IN THE NEAR FUTURE. AS THAT HAPPENS, WE DO EXPECT SOME SHOWER AND T-STORM ACTIVITY. A LEAD SHORT WAVE COMBINED WITH A SURFACE WARM FRONT PUSHING NORTHEASTWARD TONIGHT WILL CAUSE SHOWERS AND T-STORMS OVERNIGHT TONIGHT. THERE DOES SEEM TO BE SOMEWHAT OF A LOW LEVEL JET AIMED TOWARD THE MID-ATLANTIC AND NORTHEAST STATES LATE TONIGHT AND EARLY TOMORROW. BECAUSE OF THESE FACTORS, WE DO HAVE TO BE ON GUARD FOR LOCALLY HEAVY RAIN WITH ANY SHOWER OR T-STORM.

THERE MAY BE A BRIEF LULL IN THE ACTION BEFORE NEW SHOWERS AND T-STORMS DEVELOP TOMORROW AFTERNOON AND CONTINUE INTO TOMORROW NIGHT, IN RESPONSE TO THE MAIN UPPER LEVEL TROF COMING OUT. THE GFS SEEMS TO BE MORE PROGRESSIVE WITH THAT FEATURE THAN THE NAM, WHICH IS STRONGER AND DEEPER WITH THE TROF. THE EURO AND CANADIAN MAY BE SOMEWHERE IN BETWEEN. THE BOTTOM LINE IS THAT WE STILL HAVE TO KEEP THINGS UNSETTLED ON WEDNESDAY WITH AT LEAST THE CHANCE OF AN ADDITIONAL SHOWER OR T-STORM . JUST HOW MUCH MOISTURE IS AROUND AND HOW ACTIVE IT IS ON WEDNESDAY WILL DETERMINE HOW HIGH OUR TEMPS GO THAT DAY.

IT DOES APPEAR THAT BY THURSDAY, THE ATMOSPHERE WILL BECOME MORE CAPPED AS HEIGHTS RISE A BIT AND TEMPS ALOFT BECOME A LITTLE WARMER. IN ADDITION, THE AIR MASS IN GENERAL SEEMS TO BE DRIER ON THURSDAY. WE CAN'T TOTALLY RULE OUT A POP-UP CELL IN SPOTS THURSDAY AFTERNOON AND EVENING, BUT OVERALL IT SEEMS TO BE A DRIER DAY. ANY REDUCTION IN DEW POINTS ON THURSDAY WILL BE MINIMAL, AND ALSO SHORT-LIVED.

WE DO EXPECT BUILDING HEAT AGAIN LATER THIS WEEK, WITH OUR HOTTEST WEATHER PROBABLY OCCURRING ON FRIDAY. OUR NEXT BEST SHOT AT T-STORMS WILL COME WITH THE ARRIVAL OF THE NEXT FRONTAL SYSTEM...ALL BE IT A WEAK FRONT. HOWEVER, AT THIS JUNCTURE, THERE ARE STILL A LOT OF UNCERTAINTIES ON THE EXACT TIMING OF THAT FEATURE.