Severe Storm Outlook Narrative (AC)
Issued by NWS
ACUS48 KWNS 290758
SPC AC 290756
Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0256 AM CDT Wed Mar 29 2017
Valid 011200Z - 061200Z
...Day4/Sat - OK/TX...
Current water vapor loops show a well-defined shortwave trough
roughly 1000nm off of the coast of northern CA. This feature is
forecast to deepen over the western states later this week and
affect the southern plains beginning Saturday. Southerly low level
winds will increase ahead of the trough over TX/OK, with the surface
dryline developing from western OK into central TX. This will be
the focus of scattered thunderstorms. Current indications are that
sufficient instability and shear will be present in this corridor on
Saturday for a risk of severe storms.
...Day5/Sun - TX into the ArkLaMiss region...
Models become a little more divergent in solutions on Sunday, but
generally depict the development of a surface low over east TX. An
associated low-level jet will lift northward across LA, helping to
spread rich tropical moisture inland across the warm sector. Strong
winds aloft and favorable moisture/instability profiles suggest a
risk of organized severe storms over southeast TX, much of LA,
western MS, and southern AR on Sunday.
...Day6/Mon thru Day8/Wed - Southeast states...
Beyond Day5, model disagreement becomes too large to confidently
forecast daily areas of severe storm risk. However, given the
strong upper system and ample low level moisture/instability that
will likely be present, severe risk areas are expected to be
delineated in later updates for early next week over parts of the