yoda Posted July 8, 2015 Share Posted July 8, 2015 SLGT risk on 1730 SPC OTLK for just about all LWX CWA Link to comment Share on other sites More sharing options...
yoda Posted July 8, 2015 Author Share Posted July 8, 2015 here are the NAM and GFS soundings valid at 21z tomorrow. You can see why the supercell index values are so high - that is excellent low-level shear in the NAM. The GFS has veered low-level flow, so the profile ends up more unidirectional with some modest speed shear. The more westerly low-level flow may explain why the model mixes out the boundary layer so much. The picture you posted won't come up for me... it says forbidden and no access Link to comment Share on other sites More sharing options...
high risk Posted July 8, 2015 Share Posted July 8, 2015 for comparison with my previous post, here is the same NAM/GFS comparison for 18z tomorrow. The NAM low-level shear is horrid. The change in the low-levels between 18 and 21z is dramatic. Link to comment Share on other sites More sharing options...
high risk Posted July 8, 2015 Share Posted July 8, 2015 sorry about that. I think I fixed it?? The picture you posted won't come up for me... it says forbidden and no access Link to comment Share on other sites More sharing options...
yoda Posted July 8, 2015 Author Share Posted July 8, 2015 sorry about that. I think I fixed it?? Yes you did, thanks Link to comment Share on other sites More sharing options...
Kmlwx Posted July 8, 2015 Share Posted July 8, 2015 Question is can we buy the NAM and is it even remotely correct? Link to comment Share on other sites More sharing options...
Ellinwood Posted July 8, 2015 Share Posted July 8, 2015 NAM low-level winds becoming more and more westerly as time progresses. Over the course of the last 4 NAM runs, surface winds have gone from SSE to SSW to SW. Trending more and more towards the GFS wind field. Link to comment Share on other sites More sharing options...
Kmlwx Posted July 8, 2015 Share Posted July 8, 2015 NAM low-level winds becoming more and more westerly as time progresses. Over the course of the last 4 NAM runs, surface winds have gone from SSE to SSW to SW. Trending more and more towards the GFS wind field. Well if that turns out to be the case it'll just be another chapter in how we can fail at getting good setups. Hopefully GFS will nudge towards the NAM a bit - probably not. Link to comment Share on other sites More sharing options...
yoda Posted July 8, 2015 Author Share Posted July 8, 2015 Afternoon AFD from LWX .SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...THURSDAY START OUT WARM AND HUMID WITH THE FRONT LIFTING BACKNORTH INTO PENNSYLVANIA AS A WAVE OF LOW PRESSURE MOVES EASTWARDALONG IT. THE LOW WILL BE DUE NORTH OF THE AREA BY THURSDAYEVENING AND DRAG THE COLD FRONT ACROSS OUR AREA THURSDAY NIGHT.THERE IS SOME PRETTY DECENT SUPPORT ALOFT WITH THE RIGHT REAR JETQUAD AND STRONG CAPE VALUES (OVER 2000 J/KG) DEPENDING ON WHATMODEL YOU LOOK AT. ALSO QUITE A BIT OF SHEAR ON SOMEGUIDANCE...BOTH SPEED AND DIRECTIONAL. WITH THE FLOW ALSO A BITSOUTH OF WEST...THERE IS POTENTIAL FOR SOME STRONG TO SEVERETHUNDERSTORMS. THIS HAS BEEN HIGHLIGHTED BY SPC WITH A SLIGHT RISKOF SEVERE WEATHER ON THURSDAY. MAIN THREAT WOULD APPEAR TO BEDAMAGING WINDS. HIGHS WILL BE IN THE LOW 90S IN MUCH OF THE AREA. Link to comment Share on other sites More sharing options...
yoda Posted July 8, 2015 Author Share Posted July 8, 2015 15z SREFs look decent... mean sup composite parameter is >6 at 21z Link to comment Share on other sites More sharing options...
AmericanWxFreak Posted July 9, 2015 Share Posted July 9, 2015 How'd the 00z NAM look? Link to comment Share on other sites More sharing options...
yoda Posted July 9, 2015 Author Share Posted July 9, 2015 How'd the 00z NAM look? Pretty decent to me when checking the soundings out across N VA into C MD Link to comment Share on other sites More sharing options...
yoda Posted July 9, 2015 Author Share Posted July 9, 2015 0600 SPC OTLK disco ..MID ATLANTIC REGION WATER VAPOR AND RADAR LOOPS SHOW A SHORTWAVE TROUGH PRESENTLY MOVING ACROSS MO/IL. THIS FEATURE WILL TRACK NORTHEASTWARD AND INTO OH/WV BY MORNING...AND EASTWARD ACROSS PARTS OF PA/MD/VA DURING THE AFTERNOON. A MOIST AIR MASS IS IN CURRENTLY PLACE OVER THE MID ATLANTIC REGION WITH DEWPOINTS IN THE LOW 70S. POCKETS OF STRONG HEATING WILL LIKELY DEVELOP LATER TODAY...YIELDING AFTERNOON MLCAPE VALUES OF 1000-1500 J/KG. FORECAST SOUNDINGS IN THIS REGION SHOW AMPLE DEEP-LAYER VERTICAL SHEAR FOR ORGANIZED/ROTATING STORMS...AND FAVORABLE LOW LEVEL SHEAR FOR A RISK OF ISOLATED TORNADOES. DAMAGING WINDS WILL ALSO BE A THREAT AS OUTFLOWS MERGE/CONGEAL DURING THE LATE AFTERNOON AND EVENING. Link to comment Share on other sites More sharing options...
yoda Posted July 9, 2015 Author Share Posted July 9, 2015 Link to comment Share on other sites More sharing options...
mattie g Posted July 9, 2015 Share Posted July 9, 2015 So another northern MD and PA special? Link to comment Share on other sites More sharing options...
yoda Posted July 9, 2015 Author Share Posted July 9, 2015 So another northern MD and PA special? IMO, anyone north of a line from EZF to Culpepper to Luray to Moorefield WV should have a good shot at severe weather today Link to comment Share on other sites More sharing options...
mappy Posted July 9, 2015 Share Posted July 9, 2015 So another northern MD and PA special? that will go severe after passing me -- haven't a good thunderstorm all summer. lots of near misses Link to comment Share on other sites More sharing options...
yoda Posted July 9, 2015 Author Share Posted July 9, 2015 Already over 500 SBCAPE this morning Link to comment Share on other sites More sharing options...
yoda Posted July 9, 2015 Author Share Posted July 9, 2015 Link to comment Share on other sites More sharing options...
yoda Posted July 9, 2015 Author Share Posted July 9, 2015 1300 SPC disco DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0752 AM CDT THU JUL 09 2015 VALID 091300Z - 101200Z ...THERE IS AN ENH RISK OF SVR TSTMS OVER CNTRL/ERN PA AND SURROUNDING PARTS OF NRN MD/ERN WV/NRN DE/NJ... ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE CNTRL APPALACHIANS INTO NJ... ...THERE IS A MRGL RISK OF SVR TSTMS FROM THE UPR OH VLY TO THE MID-ATLANTIC CST... ...THERE IS A MRGL RISK OF SVR TSTMS FROM THE GRT BASIN THROUGH THE SRN RCKYS INTO PARTS OF THE SRN PLNS/OZARKS... ..SUMMARY STRONG TO SEVERE THUNDERSTORMS WITH DAMAGING WIND AND POSSIBLY A FEW TORNADOES ARE EXPECTED TODAY OVER PARTS OF THE CENTRAL APPALACHIANS AND MID-ATLANTIC...INCLUDING THE AREAS MAINLY WEST AND NORTH OF WASHINGTON/BALTIMORE AND PHILADELPHIA. OTHER STRONG TO SEVERE STORMS MAY OCCUR FROM THE GREAT BASIN AND SOUTHERN ROCKIES INTO THE SOUTHERN PLAINS. ..SYNOPTIC SETUP SPLIT FLOW WILL PREVAIL OVER THE LWR 48 THIS PERIOD...DOWNSTREAM FROM SLOWLY PROGRESSIVE CA UPR LOW. A SHORTWAVE TROUGH IN THE LOW WILL PIVOT NE INTO SRN NV BY THIS EVE AS A DOWNSTREAM SRN BRANCH IMPULSE MOVES FROM NW OK TO WRN MO. IN THE EAST...SEASONABLY STRONG BUT LOW-AMPLITUDE SRN BRANCH DISTURBANCE THAT CROSSED THE OZARKS/LWR OH VLY YESTERDAY IS NOW OVER IND. THE TROUGH SHOULD CONTINUE ENE INTO WRN PA/MD THIS AFTN...BEFORE TURNING E OFF THE NJ CST TNGT/EARLY FRI. AT THE SFC...LOW ASSOCIATED WITH IND TROUGH WILL REACH NW PA THIS AFTN...WHILE WAVY WARM FRONT EXTENDING TO ITS E/SE EDGES N ACROSS ERN PA/NJ. COLD FRONT TRAILING WSW FROM THE LOW WILL SETTLE SLOWLY S ACROSS THE OH VLY...WHILE LEE TROUGH BECOMES BETTER DEFINED E OF THE CNTRL APPALACHIANS. THE COLD FRONT WILL BECOME STNRY OVER THE OZARKS LATER TODAY...WHILE THE WRN END REDEVELOPS NWD AS A WARM FRONT ACROSS THE SRN PLNS. ..CNTRL APPALACHIANS/MID-ATLANTIC TODAY THROUGH EARLY TNGT BAND OF SEASONABLY STRONG /40+ KT/ 700-500 MB WSW FLOW ATTENDANT TO IND UPR VORT WILL OVERSPREAD THE UPR OH VLY LATER THIS MORNING AND REACH THE MID-ATLANTIC CST BY EVE...ACCOMPANIED BY SUBSTANTIAL MOISTURE RETURN /PW INCREASING TO AOA 2.00 INCHES/. MID-LVL LAPSE RATES WILL BE WEAK. BUT GIVEN MOISTURE QUALITY...MODERATE TO STRONG SFC HEATING SHOULD BOOST MLCAPE TO AROUND 1500 J/KG...ESPECIALLY E OF THE MOUNTAINS. DEEP...UNIDIRECTIONAL WSW UPSLOPE FLOW COULD SUPPORT INTENSIFICATION OF EXISTING MID-OH VLY CONVECTIVE BAND...AND/OR DEVELOPMENT OF ADDITIONAL STORMS TO ITS EAST...OVER ERN KY/SRN OH/WV TOWARD MIDDAY. OTHER STORMS SHOULD DEVELOP LATER THIS AFTN ALONG LEE TROUGH OVER CNTRL MD/NRN VA...AND ALONG WARM FRONT OVER THE LWR SUSQUEHANNA AND DELAWARE VLYS OF CNTRL/NRN PA AND NE MD...DE...NJ. COMBINATION OF DEEP...UNIDIRECTIONAL FLOW AND RICH MOISTURE SUGGESTS THE POTENTIAL FOR BOWING SEGMENTS WITH DMGG WIND GUSTS AS THE STORMS ORGANIZE INTO A SQLN OVER WV AND WRN PORTIONS OF PA/MD THIS AFTN. IN ADDITION...ENHANCED LOW-LVL SHEAR NEAR WARM FRONT AND NEAR LEE TROUGH/WARM FRONT INTERSECTION OVER CNTRL-ERN PA AND NRN MD WILL FOSTER A CONDITIONAL RISK FOR TORNADOES WITH ANY MORE DISCRETE/SUSTAINED UPDRAFTS THAT FORM THERE. THE SVR THREAT COULD PERSIST THROUGH THIS EVE ACROSS FAR NRN MD/ERN PA AND NJ AS THE SQLN MERGES WITH THE WARM FRONTAL STORMS...FORMING AN MCS THAT MOVES OFF THE CST LATER TNGT. Link to comment Share on other sites More sharing options...
mappy Posted July 9, 2015 Share Posted July 9, 2015 sweet, enhanced bitches Link to comment Share on other sites More sharing options...
snowfan Posted July 9, 2015 Share Posted July 9, 2015 5% tor and 30% wind probs solidly in northern MD now. Link to comment Share on other sites More sharing options...
Kmlwx Posted July 9, 2015 Share Posted July 9, 2015 sweet, enhanced bitches You had me left out of it. Link to comment Share on other sites More sharing options...
yoda Posted July 9, 2015 Author Share Posted July 9, 2015 SBCAPE doing pretty well so far... 1000 in DC per 13z SPC mesoanalysis Link to comment Share on other sites More sharing options...
mattie g Posted July 9, 2015 Share Posted July 9, 2015 So another northern MD and PA special? swody1_categoricalENH7-9-15.png Link to comment Share on other sites More sharing options...
H2O Posted July 9, 2015 Share Posted July 9, 2015 fringed Link to comment Share on other sites More sharing options...
mattie g Posted July 9, 2015 Share Posted July 9, 2015 IMO, anyone north of a line from EZF to Culpepper to Luray to Moorefield WV should have a good shot at severe weather today It seems that when we're on the southern tip of any threat, storms run farther north, as if the extension of the threat outlook is extended south as a CYA measure. I'm not poo-pooing it, though, simply because I frankly don't have the knowledge to do that. I'm just going on how I perceive these things generally play out. that will go severe after passing me -- haven't a good thunderstorm all summer. lots of near misses It's been mostly heavy rain here, with one really impressive lightning display and one instance of pea-sized hail (maybe two, if my wife was correct). Very little wind to speak of. No wind *at all* save some breezy outflow a couple times. Link to comment Share on other sites More sharing options...
yoda Posted July 9, 2015 Author Share Posted July 9, 2015 Link to comment Share on other sites More sharing options...
yoda Posted July 9, 2015 Author Share Posted July 9, 2015 Link to comment Share on other sites More sharing options...
yoda Posted July 9, 2015 Author Share Posted July 9, 2015 Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.