Isolated severe weather today...

By: Zachary Labe , 2:17 PM GMT on May 03, 2008

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"Thoughts on Severe Weather Outbreak of May 3"
Good Saturday morning!!! Another very similar setup to last Saturday may occur today in which we have another cold front with a history of severe weather moving into an area with limited instibility. And in eastern Pennsylvania another strong easterly wind is making for a marine layer with fog and low clouds. Light rain showers are already dotting the landscape across Pennsylvania. As the front moves into central Pennsylvania another squall line thunderstorm event could take place. Also the simulated radars seem to indicate this event. See below for NMM simulated radar. As always I will be providing nowcast updates throughout the day. Overall though severe weather should be pretty limited with the Laural Highlands in the highest risk zone as indexes are the highest in that region. Already cloud breaks are occuring there this morning.

"Current Weather Setup"
Over 70 tornadoes have occured in the last two days as a cold front moves in from the west. A warm front is slowly moving northward trying to push back the marine layer. But so far the marine layer is winning the battle keeping easterly Pennsylvania socked in with low clouds, fog, and cool temperatures. But in central Pennsylvania the sun is out and creating high instibility. The cold front should be east of the area by 2am.

"Current Advisories"


"Current Satellite"

(Courtesy of Penn State Meteorology.)

"Current Surface Map and Weekly History of Jet Stream Position"


"Radar for Western Pennsylvania"

"Radar for Central Pennsylvania"

"Radar for Eastern Pennsylvania"


"Forecasts from Storm Prediction Center"
SPC AC 031257

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0757 AM CDT SAT MAY 03 2008

VALID 031300Z - 041200Z

...WRN/CENTRAL PA THIS AFTERNOON/EVENING...
THE PRIMARY SYNOPTIC LOW WILL LIFT NNEWD FROM LAKE SUPERIOR INTO
ONTARIO AS AN ASSOCIATED MID LEVEL TROUGH PIVOTS ENEWD FROM THE MS
VALLEY TO THE UPPER OH VALLEY BY LATE EVENING. A SURFACE COLD FRONT
WILL MOVE EWD ACROSS THE OH VALLEY TO THE APPALACHIANS BY EARLY
TONIGHT...WHILE A SEPARATE BAROCLINIC ZONE LIFTS NWD ACROSS MD/SRN
PA. WITH BOUNDARY LAYER DEWPOINTS IN THE MID-UPPER 50S AND SOME
DAYTIME HEATING IN CLOUD BREAKS...WEAK SURFACE-BASED INSTABILITY IS
EXPECTED IN A SMALL AREA NEAR THE RETREATING FRONT ACROSS
CENTRAL/WRN PA. IF SURFACE-BASED CAPE VALUES CAN EXCEED ROUGHLY 500
J/KG...THEN FORECAST HODOGRAPHS SUGGEST A FAVORABLE ENVIRONMENT FOR
ROTATING STORMS. THE UNCERTAINTY REGARDING INSTABILITY WARRANTS

"Tornado Risks"

"Hail Risks"

"Wind Risks"


"Model Analysis"
Models have done a relatively good job forecasting this storm throughout the midwest. Today indicators point to CAPE values approaching over 1000 in southcentral Pennsylvania in the Laural Highlands. Currently breaks in the clouds are giving sun inversion heating up the atmosphere to temperatures in the 70s with dewpoints in the 60s. LI indexes are in the negatives indicating thunderstorm development. Shear levels are very high so a few tornadoes cannot be ruled out.

"9z SREF Model Forecast Cape Index"


Below the NMM simulated future radar shows a squall line developing in western Pennsylvania and reaching it's max intensity in central Pennsylvania before weakening moving into eastern Pennsylvania. Rainfall amounts generally around .5inches in most areas. Locally higher amounts in areas that see heavy thunderstorms.

"NMM Future Simulated Radar"


"My Forecast for Severe Weather"
My forecast for severe weather shows the central Pennsylvania area in the area for highest threat zone. Below is my severe weather outlook map. According to recent radar images a squall line is beginning to form and intensify. All threats are today including hail, wind, and tornado. Freezing levels are less than 10,000ft today so strong updrafts will easliy be capable of pulling down hail to the surface. Shear levels are very high capable of tornadoes. And the jet stream winds are fast and low today so strong updrafts may be able to pull down the winds from the surface. As the thunderstorms move east of the Susquehanna River they will weaken and become low-topped with heavy rain the only threat. PWAT's are not too high so flash flooding shouldn't be to much of a concern.

"My Severe Weather Risk Map"


"Conclusions on Severe Weather Outbreak"
Overall ingredients are there as was the case last Saturday but the clouds are just another inhibiting factor. For those still waiting for a widespread severe weather outbreak in Pennsylvania remember that it is only early May and we have a long way to go. For today I would not be surprised to see several severe weather reports out of especially central Pennsylvania. The Johnstown-Altoona-State College-Lock Haven line is most under the gun. For Sunday I will be back to issuing the weekly formated blog for next week with full updates so look for that tomorrow. For today keep your NOAA weather radio close by and be alert to take shelter if a warning is issued for your area as isolated tornadoes are a threat today. Have a great rest of your day!!!

"Storm Reports"


"Here north of Harrisburg 2008 statistics"
(Severe Weather Stats...)
Severe Thunderstorm Watches- 0
Severe Thunderstorm Warnings- 0
Tornado Watches- 0
Tornado Warnings- 0
Total Thunderstorms- 9

(Precipitation Stats...)
Flood Watches- 2
Flood Warnings- 3
Monthly Precipitation- 3.32inches
Yearly Precipitation- 13.66inches

(Temperature Stats...)
Heat Advisories- 0
Excessive Heat Warnings- 0
90degree days- 0

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Viewing: 15 - 1

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15. Zachary Labe
1:48 PM GMT on May 04, 2008
.58inches of rain here north of Harrisburg...
Member Since: December 14, 2007 Posts: 284 Comments: 15112
14. jthal57
12:07 PM GMT on May 04, 2008
.20" rain here last night. Planted tomatoes yesterday so at least they got some rain. Just need warm sunshine now!
13. TheRasberryPatch
11:50 AM GMT on May 04, 2008
wow, a big whopping 0.03" of rain last night. now i need the sun to come out and dry out my garden so i can get my plants in the ground.
Member Since: January 26, 2007 Posts: 72 Comments: 6256
12. wfreeck
3:39 AM GMT on May 04, 2008
See Blizzard, I told you you'd get something :-)
Member Since: August 8, 2006 Posts: 124 Comments: 3535
11. TheRasberryPatch
1:53 AM GMT on May 04, 2008
you want to talk about low ceilings and fog with the atlantic moisture and cool conditions. go to the beaches along the coast when that breeze comes in. it is amazing how it cools everything down and a thick fog. then you go inland and it can be sunny and warm. i have even seen that type of setup along the beaches and you go a block or two inland and it is sunny.
i bought my plants, but didn't get them in the ground. probably should have since we have rain coming and the ground was probably just right for planting. i actually found some celery plants. i have heard the celery from the garden is so so good. the problem will be keeping the varments away.
Member Since: January 26, 2007 Posts: 72 Comments: 6256
10. Zachary Labe
12:19 AM GMT on May 04, 2008
wfreeck- Yep, here the Atlantic moisture comes in with low ceilings less than 500ft, fog around 2miles, and cool temperatures in 50s.
Member Since: December 14, 2007 Posts: 284 Comments: 15112
9. wfreeck
12:10 AM GMT on May 04, 2008
Yeah Blizzard, here in Detroit, that east or northeast wind is the death nail to all "good" weather :-(

The only exception is when I want a lake breeze front on those hot, humid, summer days :-)

You still have a chance to see a rumble of thunder this evening (which is something), so don't get too disappointed.

Member Since: August 8, 2006 Posts: 124 Comments: 3535
8. Zachary Labe
12:01 AM GMT on May 04, 2008
Well today was a poor forecast on my part. I jumped the gun on severe weather. The clouds won out and not enough surface instibility developed. But the atmospheric conditions were sure there. O well, I learned that an easterly wind does not aid well to storm development.

FLOOD ADVISORY
NATIONAL WEATHER SERVICE STATE COLLEGE PA
736 PM EDT SAT MAY 3 2008

PAC009-057-061-040230-
/X.NEW.KCTP.FA.Y.0004.080503T2336Z-080504T0230Z/
/00000.N.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BEDFORD PA-HUNTINGDON PA-FULTON PA-
736 PM EDT SAT MAY 3 2008

THE NATIONAL WEATHER SERVICE IN STATE COLLEGE PA HAS ISSUED A

* SMALL STREAM FLOOD ADVISORY FOR...
BEDFORD COUNTY...
SOUTHERN HUNTINGDON COUNTY...
FULTON COUNTY...

* UNTIL 1030 PM EDT...

* AT 736 PM EDT DOPPLER RADAR INDICATED RAIN WAS FALLING ON AREAS
THAT RECEIVED HEAVY RAIN EARLIER THIS EVENING. DOPPLER RADAR
ESTIMATES THAT UP TO 1.2 INCHES OF RAIN HAS FALLEN THIS EVENING.

* LOCATIONS IN THE ADVISORY INCLUDE BUT ARE NOT LIMITED TO BEDFORD...
BREEZEWOOD...HYNDMAN...MANNS CHOICE...MAPLETON...ORBISONIA...
RAINSBURG...SAXTON...SCHELLSBURG...SHADE GAP...SHIRLEYSBURG...
THREE SPRINGS AND WOODBURY.

THE HEAVY RAIN FROM EARLIER PROBABLY FILLED MANY CREEKS AND STREAMS.
THE ADDITIONAL RAIN EXPECTED THROUGH 9 PM MAY CREATE MINOR FLOODING
ON SOME OF THESE SMALL STREAMS.

SMALL CREEKS AND STREAMS WILL FLOOD QUICKLY...POSSIBLY COVERING ROADS
AND FLOODING NEARBY LOW AREAS.

MOST FLOOD DEATHS OCCUR IN AUTOMOBILES. NEVER DRIVE YOUR VEHICLE INTO
AREAS WHERE THE WATER COVERS THE ROADWAY. FLOOD WATERS ARE USUALLY
DEEPER THAN THEY APPEAR. JUST ONE FOOT OF FLOWING WATER IS POWERFUL
ENOUGH TO SWEEP VEHICLES OFF THE ROAD. WHEN ENCOUNTERING FLOODED
ROADS MAKE THE SMART CHOICE...TURN AROUND...DONT DROWN.

BE PREPARED TO TAKE ACTION IF THE FLOODING THREAT INCREASES...OR A
WARNING IS ISSUED.

LAT...LON 4026 7861 4025 7845 4027 7834 4025 7830
4029 7828 4044 7789 4041 7790 4037 7780
4029 7772 4027 7772 3973 7827 3972 7878
TIME...MOT...LOC 2336Z 180DEG 0KT 4012 7827
Member Since: December 14, 2007 Posts: 284 Comments: 15112
7. Zachary Labe
8:39 PM GMT on May 03, 2008
wfreeck- Lol, thanks for posting anyway.
Member Since: December 14, 2007 Posts: 284 Comments: 15112
6. wfreeck
8:35 PM GMT on May 03, 2008
Things aren't too bad, the air just SW of you is fairly unstable, and that may spill eastward, but the time of day will ruin everything :-(

Member Since: August 8, 2006 Posts: 124 Comments: 3535
5. Zachary Labe
8:29 PM GMT on May 03, 2008
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE STATE COLLEGE PA
427 PM EDT SAT MAY 3 2008

PAZ017>019-024>026-032115-
BLAIR-CAMBRIA-CLEARFIELD-HUNTINGDON-NORTHERN CENTRE-SOUTHERN CENTRE-
427 PM EDT SAT MAY 3 2008

...A STRONG THUNDERSTORM WILL AFFECT NORTHEASTERN CAMBRIA...NORTHERN
BLAIR...NORTHWESTERN HUNTINGDON...SOUTHEASTERN CLEARFIELD AND
SOUTHWESTERN CENTRE COUNTIES...

AT 423 PM EDT...NATIONAL WEATHER SERVICE METEOROLOGISTS WERE TRACKING
A STRONG THUNDERSTORM LOCATED NEAR PRINCE GALLITZIN STATE PARK...
MOVING NORTHEAST AT 31 MPH.

WIND GUSTS TO 40 MPH AND SMALL HAIL ARE POSSIBLE WITH THIS STORM.
VERY HEAVY RAIN WILL FALL FROM THIS STORM...AND WILL CAUSE WATER TO
POND ON ROADS AND QUICKLY FILL ROADSIDE DITCHES AND SMALL STREAMS.

THIS STORM WILL BE NEAR BLANDBURG AND COALPORT AROUND 435
PM...BELLWOOD AND GLEN HOPE AROUND 440 PM...TIPTON AND SINKING
VALLEY AROUND 445 PM...RAMEY AROUND 450 PM...TYRONE...HOUTZDALE AND
BRISBIN AROUND 455 PM.

THIS WILL IMPACT THE FOLLOWING CENTRAL PENNSYLVANIA INTERSTATES...
I-80 BETWEEN MILE MARKERS 134 AND 139...I-99 BETWEEN MILE MARKERS 37
AND 60. THIS WILL ALSO IMPACT THE FOLLOWING MAJOR ROADS...ROUTE
220...ROUTE 322...STATE ROAD 350.
Member Since: December 14, 2007 Posts: 284 Comments: 15112
4. Zachary Labe
8:21 PM GMT on May 03, 2008
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE STATE COLLEGE PA
409 PM EDT SAT MAY 3 2008

PAZ017-032045-
CLEARFIELD-
409 PM EDT SAT MAY 3 2008

...A STRONG THUNDERSTORM WILL AFFECT CLEARFIELD COUNTY...

AT 406 PM EDT...NATIONAL WEATHER SERVICE METEOROLOGISTS WERE TRACKING
A STRONG THUNDERSTORM LOCATED 14 MILES SOUTHWEST OF CLEARFIELD...
MOVING NORTHEAST AT 41 MPH.

WIND GUSTS TO 40 MPH AND SMALL HAIL ARE POSSIBLE WITH THIS STORM.

THIS STORM WILL BE NEAR GRAMPIAN AROUND 415 PM...CURWENSVILLE AROUND
420 PM...HYDE AND CLEARFIELD AROUND 425 PM...AND LECONTES MILLS
AROUND 440 PM.

THIS WILL IMPACT THE FOLLOWING CENTRAL PENNSYLVANIA INTERSTATES...
I-80 BETWEEN MILE MARKERS 108 AND 124.

THIS WILL ALSO IMPACT THE FOLLOWING MAJOR ROADS...ROUTE 219...ROUTE
322.
Member Since: December 14, 2007 Posts: 284 Comments: 15112
3. sullivanweather
7:31 PM GMT on May 03, 2008
Member Since: March 8, 2007 Posts: 273 Comments: 12612
2. Zachary Labe
7:14 PM GMT on May 03, 2008
Busy morning. Got all of the 21 bags of garden soil with 2 tomato plants, 4 zuchinni plants, 2 cucumber plants, 1 basil plant, 1 chive plant, 1 parsley plant, 1 pack of bean seeds, 2 packs of pea seeds, 1 pack of radish seeds, 1 pack of carrot seeds. Just got everything in the ground. In my other vegetable garden I still have lettuce growing, blueberries, onions, and more peas. So I think I am set for the summer. I will get some pictures as soon as some seeds start to mature and develop.
Member Since: December 14, 2007 Posts: 284 Comments: 15112
1. Zachary Labe
6:31 PM GMT on May 03, 2008
Thunderstorms now beginning to form...

Member Since: December 14, 2007 Posts: 284 Comments: 15112

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About Blizzard92

Cornell University- Atmospheric Sciences Undergrad; Research Assist.- Onset of Spring Indices Toolbox; Interests- Small spatial scale climatolology

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Linglestown, PA
Elevation: 520 ft
Temperature: 24.2 °F
Dew Point: 15.2 °F
Humidity: 68%
Wind: Calm
Wind Gust: 9.0 mph
Updated: 10:37 AM EST on January 18, 2014

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