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July 2012

07/31/2012

QUIET END TO JULY. STORMY START TO AUGUST.

AS WE LOOK BACK AT THIS MONTH, WE FIND THAT TEMPS AVERAGED 2.4 DEGREES ABOVE NORMAL, AND RAINFALL IS RUNNING JUST A TAD BELOW NORMAL WITH A TOTAL OF 4.21" THROUGH THE 30TH.

DURING THE MONTH OF AUGUST, NORMAL TEMPS BEGIN THEIR SLOW DOWNHILL SLIDE, AND WE LOSE ABOUT 5 DEGREES OFF OF THE NORMALS BY THE END OF THE MONTH. WE GENERALLY SEE A GRADUAL DECLINE IN THE OCCURRENCE OF T-STORMS IN AUGUST, ESPECIALLY AFTER THE 15TH OR 20TH. FROM THAT POINT ON THROUGH SEPTEMBER AND OCTOBER, OUR NORMAL PRECIP IS MORE HEAVILY DEPENDENT ON TROPICAL MOISTURE FACTORING INTO THE MIX. THE LOSS OF DAYLIGHT WILL BECOME MORE AND MORE NOTICEABLE IN THE WEEKS AHEAD, AS WE LOSE A TOTAL OF 71 MINUTES FROM THE 1ST TO THE 31ST. DESPITE THE LOWERING SUN ANGLE, SLIGHTLY FALLING NORMAL TEMPS, AND SHORTER DAYS, IT CAN STILL GET VERY HOT AND HUMID DURING AUGUST, GIVEN THE RIGHT CONDITIONS.

RECENTLY, WE'VE BEEN KIND OF STUCK IN SOME MIDDLE GEAR OF MID-SUMMER…THE HEAT AND HUMIDITY HASN'T BEEN TOO BAD, BUT, IT'S NOT COMFORTABLE EITHER. IT'S JUST THAT GENERIC FEEL. THERE WON'T BE MUCH CHANGE IN THIS SCENARIO FOR THE NEXT DAY OR TWO. THEN, TEMPS WILL TREND UPWARD SOMEWHAT BY THE END OF THE WEEK AND INTO THE UPCOMING WEEKEND. HOWEVER, IT REMAINS TO BE SEEN JUST HOW HOT IT WILL BE ABLE TO GET. IT CERTAINLY DOES NOT LOOK LIKE ANYTHING EXTREME COMING UP ANYTIME SOON. IN THE PRECIP DEPARTMENT, WE ARE ALSO DEALING WITH A VERY WISHY-WASHY, MID-SUMMER TYPE OF PATTERN THAT IS REALLY TOUGH TO NAIL DOWN WITH EXACT DETAILS. THAT BEING SAID, WE DO HAVE TO TRY TO BE AS SPECIFIC AS WE CAN IN THE SHORT TERM...NEXT 24 -48 HOURS. AFTER THAT, WE HAVE NO CHOICE BUT TO BE A BIT MORE VAGUE. EVEN WITH THE UNCERTAINTIES THAT WE FACE IN THE DAYS AHEAD, THERE ARE DEFINITELY SOME FEATURES THAT WE CAN HANG OUR HAT ON. ONE IS THE FAIRLY WELL-DEFINED WAVE OFF THE EAST COAST. THAT SYSTEM WILL BRING SOME RAIN TO EASTERN NEW ENGLAND TONIGHT, AND EVENTUALLY SOME WET WEATHER UP INTO NOVA SCOTIA AND NEW BRUNSWICK TOMORROW. ON THE WEST SIDE OF THAT LOW, THERE IS A PROTECTED ZONE THAT EXTENDS FROM MAINE SOUTHWESTWARD INTO EASTERN PA AND NJ RIGHT NOW, AS THAT IS WHERE THE SURFACE HIGH IS RIDGING. FARTHER WEST, WE SEE THE NEXT UNSETTLED ZONE SETTING UP FROM THE CENTRAL MOUNTAINS OF PA, WESTERN MD, AND WV WESTWARD INTO THE OHIO VALLEY, AND NORTHWARD INTO THE GREAT LAKES REGION. THAT AREA IS ASSOCIATED WITH THE NEXT SHORT WAVE AND WEAK SURFACE FRONT HEADING SOUTHEASTWARD IN THE FLOW. ACTIVITY ASSOCIATED WITH THAT FEATURE WILL MAKE IT EASTWARD TO A POINT TONIGHT BEFORE WEAKENING. EXACTLY WHERE THAT ENDS UP BEING IS UP FOR DEBATE, BUT THE DELAWARE RIVER MAY BE A GOOD GUIDE BY TOMORROW MORNING.

MORE SHOWERS AND T-STORMS WILL DEVELOP DURING THE DAY TOMORROW, AND THE MOST ACTIVE ZONE WILL SET UP FROM CENTRAL PA EASTWARD TO THE EAST COAST...OF COURSE, INCLUDING OUR AREA.

DRYING WILL OCCUR ALOFT. HOWEVER, WITH THE FRONTAL BOUNDARY WASHING OUT NEARBY AND SOME LOW LEVELMOISTURE REMAINING, WE STILL HAVE TO ALLOW FOR SOME POP-UP ACTIVITY AROUND THE REGION, MAINLY DURING THEAFTERNOON HOURS. THE FARTHER WEST YOU GO, SAY WEST OF THE SUSQUEHANNA VALLEY IN PA AS WELL AS WEST OFBINGHAMTON, NY, THE MORE CONFIDENT WE ARE THAT THURSDAY WILL BE A DRY DAY.

BY THURSDAY, A FAIR AMOUNT OF

LOOKING AHEAD, FRIDAY WILLLIKELY BE RAINFREE ALONG THE EAST COAST BEACHES, DUE TO A GENERAL ONSHORE FLOW THAT DAY. WITH NO REALMECHANISM TO GET CONVECTION TO FIRE UP THAT DAY, WE FEEL THAT MOST OF WHAT DEVELOPS WILL TEND TO FAVORTHE HIGHER ELEVATIONS OF THE EAST. THE SAME BASIC REGIME WILL CARRY OVER INTO THE UPCOMING WEEKEND.HOWEVER, AT SOME POINT, OUR CHANCES OF GETTING MORE WIDESPREAD T-STORMS WILL INCREASE AS THE NEXT SHORTWAVE AND COOL FRONT ARRIVE FROM THE NORTHWEST. THAT COULD BE SUNDAY, OR IT MAY WAIT UNTIL MONDAY. WE'LL LOOK AT THAT SITUATION MORE CAREFULLY IN THE DAYS AHEAD.

 

 

07/17/2012

SIZZLE, STORMS, & A STALLED FRONT

WE DEFINITELY HAVE A FULL PLATE OF WEATHER TO DEAL WITH DURING THE REST OF THIS WEEK, FOLLOWED (HOPEFULLY) BY SOME VERY NICE CONDITIONS THIS COMING WEEKEND.

THESE ARE THE MAIN, BIG TICKET ITEMS OVER THE NEXT FEW DAYS...(1) THE EXTREME HEAT AND HUMIDITY THROUGH TOMORROW. (2) THE POTENTIAL FOR STRONG TO SEVERE T-STORMS TOMORROW AFTERNOON INTO TOMORROW NIGHT. (3) THE PAINFULLY SLOW PRESS OF THE COOL FRONT SOUTHWARD AS A COUPLE OF WAVES PULSE ALONG THE FRONTAL BOUNDARY. THAT WILL LEAD TO A CONTINUATION OF UNSETTLED WEATHER THROUGH FRIDAY SOUTH OF A CERTAIN POINT.

ON THE SUBJECT OF HEAT, WE ARE DEFINITELY BAKING TODAY. HOWEVER, THE CORE OF THE HOTTEST AIR IS ACTUALLY JUST TO OUR NORTH...FROM SOUTHERN MICHIGAN INTO UPSTATE NY. THE 2 P.M. TEMP IN ANN ARBOR, MI WAS 100, AND IT HAS ALREADY HIT 100 IN SYRACUSE, NY BEFORE BACKING OFF A TAD. DESPITE THE SCORCHING HEAT IN OUR AREA

TODAY, DEW POINTS STILL AREN'T TERRIBLY HIGH. THAT IS ABOUT TO CHANGE TONIGHT AND TOMORROW AS THE FRONT SLOWLY BUT SURELY PRESSES SOUTHWARD TOWARD US. FOR THAT REASON, A VERY WARM, STUFFY NIGHT IS COMING UP TONIGHT, FOLLOWED BY A DANGEROUSLY HOT AND HUMID DAY TOMORROW. AS LONG AS NOTHING WEIRD HAPPENS, LIKE TOO MUCH CLOUDINESS OR T-STORMS OCCURRING EARLIER IN THE DAY THAN WE ARE BARGAINING FOR, HIGH TEMPS TOMORROW SHOULD BE SIMILAR TO TODAY, AND PERHAPS EVEN A TAD HOTTER IN PLACES, SINCE WE ARE PRE-FRONTAL.

ON THE SUBJECT OF SEVERE WEATHER, THERE WILL OBVIOUSLY BE SOME POTENT ACTION TAKING PLACE WELL TO OUR NORTH THIS AFTERNOON AND EARLY EVENING...ACROSS NORTHERN NY STATE AND INTO NORTHERN NEW ENGLAND, AS THE SURFACE LOW RUNS EASTWARD FROM THE ST. LAWRENCE VALLEY INTO THE MARITIME PROVINCES BY TOMORROW. PRESSURES ARE QUITE LOW UP THAT WAY, AND IN SOME LOCATIONS, THERE IS ENOUGH VERTICAL WIND SHEAR TO SUPPORT ISOLATED TORNADOES. THAT ACTIVITY WILL PROGRESS SOUTHWARD FOR AWHILE TONIGHT BEFORE WEAKENING AND THEN PERHAPS DYING OUT OVERNIGHT. OBVIOUSLY, WE

DO EXPECT NEW T-STORMS TO FIRE UP ALONG AND AHEAD OF THE FRONT TOMORROW. SOMETHING WE WILL HAVE TO WATCH IS A PRE-FRONTAL TROF DEVELOPING TOMORROW EAST OF THE MOUNTAINS, DUE TO THE EXTREME HEAT.  IF THAT DOES INDEED HAPPEN, THEN WE HAVE TO BE ON GUARD FOR T-STORMS DEVELOPING WELL AHEAD OF THE ACTUALCOOL FRONT AND MAYBE EARLIER THAN WE ARE BARGAINING FOR.

THE MAIN THREAT TOMORROW SEEMS TO BE DAMAGINGWINDS (MOSTLY STRAIGHT LINE) AND HAIL, ALTHOUGH FREEZING LEVELS MAY BE JUST A BIT TOO HIGH FOR FREQUENT HAILOCCURRENCE. WHILE A TORNADO CAN'T BE TOTALLY RULED OUT TOMORROW AFTERNOON AND EVENING, THE THREAT SEEMSSMALLER THAN IT DOES THIS AFTERNOON WAY UP TO OUR NORTH IN THAT BOX AREA.

THERE IS NOW INCREASING EVIDENCETHAT THE FRONT IS GOING TO HAVE A VERY TOUGH TIME PUSHING SOUTHWARD WEDNESDAY NIGHT, THURSDAY, AND EVENINTO FRIDAY. FOR THAT REASON, WE HAVE TRENDED FORECASTS ACROSS THE BOARD MORE PESSIMISTIC SOUNDING FORTHAT PERIOD. WE ALSO NUDGED SOME TEMPS DOWN LATER THIS WEEK, PARTICULARLY FOR FRIDAY. IT WOULDN'T BE SHOCKING TO SEE CLOUDS LINGER INTO EARLY SATURDAY, BUT WE FEEL DRIER AIR WILL WIN OUT FOR THE MAJORITY OF THE WEEKEND.

07/09/2012

HEAT & HUMIDITY ON HOLD

ON THIS DATE BACK IN 1936, THE TEMP IN CENTRAL PARK REACHED A SCORCHING 106 DEGREES. THAT IS STILL THE ALL-TIME RECORD HIGH FOR NYC. JULY 9TH, 1936 IS ALSO THE HOTTEST DAY ON RECORD FOR A FEW OTHER LOCATIONS IN THE NORTHEAST, INCLUDING WILKES-BARRE/SCRANTON, PA WITH A 103. WHEN YOU THINK ABOUT IT, HEAT WAVES AT THIS TIME OF YEAR CAN CERTAINLY BE VERY POTENT. THE SUN IS STILL REALLY STRONG AND HIGH IN THE SKY, AND MANY YEARS IT DOES TAKE UNTIL EARLY JULY FOR THE ATMOSPHERE TO REALLY TRANSITION INTO A MATURE SUMMERTIME MODE. OF COURSE, A STRETCH OF DRY WEATHER PRECEDING THE HEAT WAVE CERTAINLY AIDS IN GETTING THE EXTREME HEAT. WE CERTAINLY JUST DEALT WITH A PRETTY IMPRESSIVE HEAT WAVE. HOWEVER, IT WAS NOT AS STIFLING AS IT WAS JUST TO OUR SOUTH. IN WASHINGTON, DC, FOR EXAMPLE, THEY HAD FOUR DAYS IN A ROW WITH 100 DEGREE PLUS HEAT, SATURDAY BEING THE HOTTEST OF THE BUNCH WITH A RECORD-BREAKING 105 DEGREES! BEFORE TODAY, THE LOWEST DAYTIME MAX THAT DCA HAD WAS A 95 ON THE 2ND. THROUGH YESTERDAY, THE TEMP DEPARTURE FOR THE MONTH IS +9.6 DEGREES, WHICH IS AMAZING FOR THIS TIME OF YEAR. WITH A COUPLE OF EXCEPTIONS (PHL PERHAPS ONE), THE HEAT WAVE HAS BEEN BROKEN TODAY.

 

 

 

 

 

 

 

 

 

 

 

 

NO MORE BAKING HEAT IS ON THE WAY ANYTIME SOON. HOWEVER, BY THE SECOND HALF OF THIS UPCOMING WEEKEND AND INTO EARLY NEXT WEEK, WE COULD BE DEALING WITH VERY WARM TO HOT WEATHER (BUT NOT EXTREME) ONCE AGAIN WITH PRETTY HIGH HUMIDITY LEVELS. THE OVERALL PATTERN SEEMS TO FEATURE A SPLIT IN THE UPPER LEVEL HIGHS, WITH ONE REALLY STRONG CENTER OUT OVER THE SOUTHWESTERN STATES, AND ANOTHER CENTER SETTING UP OFF THE EAST COAST...THE CLASSIC BERMUDA HIGH. IN BETWEEN THESE TWO UPPER LEVEL HIGHS WILL BE A RELATIVE WEAKNESS IN THE FLOW. OVER TIME, WE WILL EVENTUALLY HAVE TO DEAL WITH THIS LATER THIS WEEK AND MAYBE INTO THE START OF THE WEEKEND.

AS WE TRANSITION FROM THE RELATIVELY COMFORTABLE DEW POINT AIR OF THE NEXT FEW DAYS INTO THE STICKY CONDITIONS OVER THE WEEKEND, WE COULD HAVE TO DEAL WITH A PERIOD OF MORE EXTENSIVE CLOUDINESS AND PERHAPS MORE WIDESPREAD SHOWER AND T-STORM ACTIVITY. THERE IS CERTAINLY A LOT OF DEBATE AS TO HOW THIS WILL ALL UNFOLD. WILL WE GO THROUGH A VERY WET STRETCH BEFORE WE MORPH INTO STANDARD BERMUDA HIGH WEATHER, OR WILL THE TRANSITION BE RELATIVELY EASY AND UNEVENTFUL, AS THE MAIN CORRIDOR OF MOISTURE SETS UP TO OUR NORTH AND WEST INTO THE APPALACHIAN MOUNTAINS AS WELL AS THE OHIO VALLEY AND GREAT LAKES REGION? THAT IS OBVIOUSLY AN ISSUE THAT WE WILL HAVE TO RESOLVE AS WE GO THROUGH THIS WEEK. BEFORE THE VERY WARM, MUGGY WEATHER SETTLES IN AGAIN, IT IS FAIRLY LIKELY THAT THERE WILL BE AT LEAST ONE DAY AND MAYBE TWO LATER THIS WEEK DURING WHICH TEMPS ARE TRIMMED BACK SOMEWHAT DUE TO MORE MOISTURE AND A WIND COMPONENT OFF THE WATER. 

 UNTIL THEN, THE SHORT TERM WILL BE RATHER SIMPLE AND STRAIGHTFORWARD WEATHER WISE. THE FRONTAL BOUNDARY TOOUR SOUTH IN NC..THE WIND SHIFT LINE, AND NOT THE TRUE DEW POINT FRONT WHICH IS STILL UP ACROSS VA AND THEDELMARVA PENINSULA...HAS A WEAK SURFACE WAVE ON IT. THAT FEATURE WILL RUN OFF THE NC COAST TOMORROW,ALLOWING THE FRONTAL BOUNDARY TO SINK A BIT FARTHER SOUTHWARD. THAT, IN TURN, WILL ALLOW FOR A BIT MORE OF ASOUTHWARD PUSH OF LOWER DEW POINT AIR. MEANWHILE, A WEAK UPPER LEVEL SHORT WAVE WILL CROSS THE NORTHEASTTOMORROW. WITH VERY LIMITED OR NO SURFACE CONVERGENCE, AND RATHER LOW DEW POINTS FOR JULY STANDARDS, WEARE NOT TOO IMPRESSED WITH MUCH HAPPENING FROM THAT SYSTEM. EVEN SO, WE DO HAVE TO ALLOW FOR AT LEAST AFEW STRAY SHOWER/T-SHOWER CELLS TO POP UP TOMORROW AFTERNOON AND EVENING, ESPECIALLY OVER THE HIGHGROUND TO OUR NORTH AND WEST. ASIDE FROM THAT, WE ARE BASICALLY LOOKING AT DRY WEATHER EACH OF THE NEXTTHREE DAYS WITH AT LEAST SOME SUN EACH DAY AND NOT A WHOLE LOT OF TEMP VARIATION FROM ONE DAY TO THE NEXT.TONIGHT WILL DEFINITELY BE MORE COMFORTABLE THAN RECENT NIGHTS WITH THAT LOWER DEW POINT AIR OVERSPREADINGTHE AREA.