Mesoscale Discussion 0697
NWS Storm Prediction Center Norman OK
0249 PM CDT Thu May 11 2017
Areas affected...Far Eastern Oklahoma...Arkansas...Far Southeast
Kansas...Southern Missouri
Concerning...Severe Thunderstorm Watch 208...
Valid 111949Z - 112145Z
The severe weather threat for Severe Thunderstorm Watch 208
continues.
SUMMARY...A severe threat is expected to develop across parts of far
eastern Oklahoma, much of Arkansas and into southern Missouri. Large
hail and wind damage are expected to be the primary threats. A new
weather watch will likely be needed to the east of WW 208 within the
hour.
DISCUSSION...The latest surface analysis shows a 1008 mb low in
central Oklahoma with a moist airmass located to the east of the low
across eastern Oklahoma and Arkansas. Surface dewpoints across this
area are generally in the mid to upper 60s F with the RAP estimating
MLCAPE values in the 2000 to 3000 J/kg range. Severe thunderstorms
are ongoing in the central part of WW 208 just to the west of where
the strongest instability is analyzed. The wind shear environment in
the vicinity of these storms is sampled well by the Tulsa WSR-99D
VWP which shows 0-6 km shear of 50 kt and some veering of winds with
height in the lowest 2 km AGL. This combined with 700-500 mb lapse
rates near 8.0 C/km will support supercells with large hail.
Supercells should also be associated with a wind damage threat. This
convection is forecast to maintain a severe threat, moving
northeastward into southwest Missouri. Thunderstorms will also
likely intensify southward across western and central Arkansas over
the next couple of hours. Moderate to strong deep-layer shear and
steep mid-level lapse rates in this area will also make supercells
with large hail possible. Short bowing line segments may also
develop and be accompanied by a wind damage threat.
..Broyles.. 05/11/2017
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...MEG...LZK...SGF...SHV...TSA...
LAT...LON 37369146 37469476 36109518 34469459 33959387 33929273
34649173 35779104 37369146
Read morefrom SPC Forecast Products http://ift.tt/JjWC9g
No comments:
Post a Comment