spc ac 070634
day 2 convective outlook
nws storm prediction center norman ok
1234 am cst sat dec 07 2019
valid 081200z - 091200z
...no severe thunderstorm areas forecast...
severe thunderstorms are not expected sunday.
a northern-stream shortwave trough is expected to move across the
northern rockies into the northern/central plains on sunday. at the
same time, a low-amplitude southern-stream shortwave trough will
eject quickly in northern portions of the southern plains while
another more amplified shortwave trough moves southward across ca.
as a result of this evolution, the overall upper pattern is expected
to undergo substantial deepening and by early monday morning upper
troughing will likely extend from the hudson bay southwestward
through southern ca.
surface pattern early sunday will likely feature lee troughing
across the high plains and high pressure along the east coast.
cyclogenesis is anticipated across the central high plains with the
resulting low moving across northern ok overnight sunday and into
monday morning. modest moisture return is anticipated from the tx
coastal plain into the arklatex, although warm temperatures aloft
should preclude deep convection.
three different regions have some potential for isolated
thunderstorms. the first is from central ca into the great basin
where cold mid-level temperatures will support modest instability
amidst persistent forcing for ascent. thunderstorm coverage in this
area is expected to be over 10%, which merits delineation of a
general thunder areas.
the second area is across the mid ms valley where gradually
increasing mid-level moisture and persistent forcing for ascent may
result in a few updrafts deep enough to support lightning. however,
coverage is currently expected to remain less than 10%.
the last area is along the carolina coast where returning low-level
moisture will help support modest instability. low-level confluence
within this moist environment will result in showers but updrafts
are currently expected to remain too shallow for charge separation
and lightning production.
...maximum risk by hazard...
tornado: wuus02 ptsdy2 product
note: the next day 2 outlook is scheduled by 1730z