MCS sobre Tennessee y algunas celdas severas entre el norte de Georgia y el oeste de South Carolina. Esta zona, esta bajo un enhanced risk.
Link al tweet
Riesgos importantes: vientos y granizos. Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0237 PM CDT Tue Mar 21 2017
Valid 212000Z - 221200Z
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM MIDDLE TO
SOUTHEAST TENNESSEE THROUGH NORTHEAST ALABAMA INTO NORTHERN
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE TENNESSEE
VALLEY INTO THE SOUTHERN APPALACHIAN AREA...
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE LOWER
MISSISSIPPI VALLEY THROUGH A PORTION OF THE CAROLINAS...
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER THE
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ALONG THE
NORTHWEST CALIFORNIA COAST...
Hail and damaging thunderstorm wind gusts are expected today mainly
across the Tennessee Valley to the southern Appalachians. An
enhanced corridor of severe winds and hail may occur this afternoon
and evening from middle Tennessee to northeastern Alabama and
northern Georgia. An isolated severe storm or two, capable of hail,
damaging gusts and/or a tornado, may develop also across portions of
the California Central Valley and the northwest California coast.
...Tennessee Valley area...
A cluster of thunderstorms continues developing over northwest TN in
association with a progressive, low-amplitude shortwave trough. The
downstream boundary layer is destabilizing with strong diabatic
heating promoting 1500 J/kg MLCAPE. Storms will soon become surface
based and evolve into a forward propagating MCS capable of producing
damaging wind and large hail. See swomcd 302 and severe thunderstorm
watch 76 for more information.
...Sacramento Valley and the northwest California coast...
Storms developing over the Sacramento valley will pose a marginal
risk for hail and perhaps a brief tornado. Have also introduced a
marginal risk category for the possibility of a brief tornado over
the northwest California coast where the atmosphere is destabilizing
downstream from a zone of ascent associated with a shortwave trough
just offshore. See swomcd 301 and 303 for more information.
.PREV DISCUSSION... /ISSUED 1127 AM CDT Tue Mar 21 2017/
...Mid MS Valley to the Southeast States...
The morning surface analysis shows a weak frontal boundary extending
from a low over OK into northern AR and TN. A cluster of
thunderstorms has developed this morning near the front over
southwest MO, where isolated severe hail has occurred. These storms
have weakened somewhat in the short-term, but are expected to
intensify again this afternoon as strong daytime heating
destabilizes the air mass over northeast AR and west TN. 12z model
guidance is very consistent in depicting these storms organizing
into an MCS that tracks east-southeastward across much of TN,
northern AL and eventually into northern GA. Forecast soundings
along this corridor show favorable parameters for large hail, and
increasing mesoscale organization will likely enhance the risk of
damaging winds later today. Therefore will maintain the ENH risk
area. The storms are expected to weaken after sunset over SC.
Scattered thunderstorms are expected this afternoon and evening over
the Sacramento Valley of northern CA. It is unclear how much
destabilization will occur in this region, as clouds and showers are
prevalent at this time. However, forecast soundings suggest
favorable vertical shear profiles and mid level lapse rates will be
present. This will result in a risk of a few strong cells capable
of hail, damaging winds, and/or a tornado or two. Some low risk of
severe storms extends northeastward into parts of northern NV,
eastern OR, and southern ID as well. However, will not extend MRGL
risk into these areas due to cloud cover and limited instability.
A las 01:00z, se actualiza.