MD 0002 CONCERNING SEVERE POTENTIAL…WATCH UNLIKELY FOR PARTS OF SOUTHWEST INTO SOUTH-CENTRAL AZ
Mesoscale Discussion 0002
NWS Storm Prediction Center Norman OK
0247 PM CST Sun Jan 01 2023
Areas affected...Parts of southwest into south-central AZ
Concerning...Severe potential...Watch unlikely
Valid 012047Z - 012315Z
Probability of Watch Issuance...5 percent
SUMMARY...Strong to locally severe gusts and perhaps small hail
could affect portions of southwest into south-central AZ this
afternoon. A watch is not expected.
DISCUSSION...Latest regional radar data shows a shallow, loosely
organized broken line of convection tracking east/northeastward at
around 40 mph across southwest AZ. This activity is generally
focused along/ahead of an eastward-advancing Pacific cold front,
which will continue overspreading southwest and south-central AZ
this afternoon. Immediately ahead of the convective line, cloud
clearing has allowed for modest diurnal heating/destabilization amid
lower/middle 50s dewpoints. These boundary-layer conditions should
support surface-based inflow (per RAP/NAM forecast soundings) for
these storms (and an additional band of storms tracking eastward
along the International Border) this afternoon.
While storms have struggled to substantially intensify thus far,
increasing large-scale ascent (per water vapor loops) and cooling
aloft/steepening midlevel lapse rates could favor a modest uptick in
convective intensity with eastward extent during the next few hours.
In addition, 30-45 kt of effective shear oriented oblique to the
cold front (and convective outflow boundaries) should also aid in
the maintenance of storms. With all that said, widespread cloud
coverage over much of the warm sector and limited instability
(200-400 J/kg MLCAPE) continues to cast uncertainty on the potential
for any more than locally strong gusts (40-50 mph) and perhaps small
hail with this activity. A watch is not expected this afternoon.
..Weinman/Hart.. 01/01/2023
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...TWC...FGZ...PSR...
LAT...LON 32191332 32861327 33091318 33541303 33961279 34111272
34241251 34201190 33931154 33291152 32361165 31831195
31651218 31791295 31961327 32191332
