Mesoscale Discussion 17

Issued

Jan 10, 2016, 5:43 AM EST (10:43 UTC)

Expired

Jan 10, 2016, 8:15 AM EST

In force

3 hr

Issued by

the Storm Prediction Center

Chance of a watch

20%

Counties Beaufort County, NC, Camden County, NC, Carteret County, NC, Craven County, NC, Currituck County, NC, Dare County, NC, Hyde County, NC, Pamlico County, NC, Pasquotank County, NC, Perquimans County, NC, Tyrrell County, NC, Washington County, NC

The Morehead City radar (KMHX), 21 km from the middle of the area, began a volume at 10:42 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

884 
ACUS11 KWNS 101043
SWOMCD
SPC MCD 101043 
NCZ000-101315-

MESOSCALE DISCUSSION 0017
NWS STORM PREDICTION CENTER NORMAN OK
0443 AM CST SUN JAN 10 2016

AREAS AFFECTED...FAR EASTERN NC /INCLUDING THE OUTER BANKS/

CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY 

VALID 101043Z - 101315Z

PROBABILITY OF WATCH ISSUANCE...20 PERCENT

SUMMARY...AN ISOLATED TORNADO AND/OR DAMAGING-WIND THREAT IS
EXPECTED ACROSS FAR EASTERN NC INCLUDING THE OUTER BANKS THROUGH MID
TO LATE MORNING.  OVERALL FORECAST FOR LOW COVERAGE OF THE
SEVERE-WEATHER THREAT PRECLUDES THE NEED FOR A WATCH AT THIS TIME.

DISCUSSION...OBJECTIVE ANALYSES DURING THE OVERNIGHT INDICATED THE
ENVIRONMENT IN THE WAKE OF THE TSTMS THAT MOVED ACROSS PAMLICO SOUND
AND THE OUTER BANKS BETWEEN 0530-0730Z HAS DESTABILIZED.  VWP DATA
AT MHX AND ILM SHOWED 850-MB AND 700-MB WINDS VEERED TO
SOUTHWESTERLY IN THE WAKE OF THE EARLIER STORMS ALLOWING FOR GREATER
THETAE/STEEPER SURFACE TO 3-KM MLCAPE OF 100-150 J/KG TO SPREAD
NORTHWARD FROM OFFSHORE THE SOUTHERN NC COASTAL AREA.  SINCE
0830Z...MOSAIC RADAR IMAGERY SHOWED AN INCREASE IN CONVECTIVE
DEVELOPMENT APPROXIMATELY 30-40 NM OFFSHORE THE CENTRAL SC COAST TO
THE CENTRAL NC COAST. THE SOUTHERN EXTENT OF THIS ACTIVITY APPEARED
TO BE LOCATED WITHIN A CONFLUENCE ZONE PER SURFACE STREAMLINE
ANALYSIS...WHILE MINI-SUPERCELLS WERE LOCATED TO THE SOUTH AND
SOUTHEAST OF THE OUTER BANKS IN VICINITY OF THE MARINE FRONT.

50-60-METER 500-MB HEIGHT FALLS WILL SPREAD ACROSS EASTERN NC
THROUGH THIS MORNING AS THE SOUTHERN EXTENT OF THE PRIMARY SHORTWAVE
TROUGH TRACKING INTO THE UPPER OH VALLEY/CENTRAL APPALACHIANS
APPROACHES THIS REGION.  THIS COMBINED WITH FORCING FOR ASCENT
WITHIN THE EXIT REGION OF A STRENGTHENING SWLY MID-UPPER-LEVEL JET
SPREADING INTO THE EASTERN CAROLINAS/SOUTHEAST VA THIS MORNING
SHOULD SUPPORT ADDITIONAL TSTM DEVELOPMENT THROUGH 12-15Z.  STRONG
DEEP-LAYER SHEAR WILL FAVOR ORGANIZED/ROTATING UPDRAFTS AS CURRENTLY
OBSERVED OFFSHORE PER RADAR IMAGERY.  INCREASED HODOGRAPH CURVATURE
WILL BE SUSTAINED GIVEN A 40-50-KT SLY LOW-LEVEL JET SUPPORTING A
TORNADO THREAT.  WEAK INSTABILITY IS EXPECTED TO LIMIT THE COVERAGE
OF STRONGER TO SEVERE STORMS.  THIS AND SPATIOTEMPORAL LIMITS
PRECLUDE THE NEED FOR A SEVERE-WEATHER WATCH.  

SEVERAL OF THE CAMS AND LAST FEW RUNS OF THE HRRR SUPPORT THIS
SCENARIO WITH STRONGER UH TRACKS TENDING TO REMAIN OFFSHORE.  BY
14-16...SURFACE TO 800-MB WINDS ARE EXPECTED TO HAVE MORE OF A
WESTERLY COMPONENT WHICH SHOULD REDUCE HODOGRAPH CURVATURE...AND
ALSO EFFECTIVELY SHIFT THE CORRIDOR OF LOW-LEVEL CONFLUENCE EAST AND
OFFSHORE.

..PETERS/EDWARDS.. 01/10/2016

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...AKQ...MHX...ILM...

LAT...LON   33757787 34537749 35557699 36377643 36517577 35917527
            35297538 34797595 34507641 33967723 33687754 33757787

Mesoscale Discussions in North Carolina, 2016Every mesoscale discussion in 2016

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.