Valid 061200Z – 071200Z
…THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS EASTERN AZ TO
PORTIONS OF WEST TX…
…SUMMARY…
Isolated severe thunderstorms are possible from eastern Arizona to
western portions of Texas, mainly during the late afternoon to
mid-evening.
…Southeast AZ to West TX…
A mid-level low over Baja CA will slowly decay as it evolves into an
open wave across AZ and NM. However, a belt of confluent mid-level
west-southwest flow will persist downstream of this wave through
this evening, supporting effective bulk shear from 35-50 kt.
Isolated elevated convection will be ongoing across parts of AZ/NM
at 12Z this morning and likely persist east throughout the day as
700-mb warm/moist advection continues. This activity should temper
the northern extent of surface-based destabilization and aid in
reinforcing a differential heating zone across the Permian Basin to
the Low Rolling Plains of western North Texas. Near this effective
baroclinic zone, a corridor of modest buoyancy should develop with
MLCAPE approaching 1000-1500 J/kg in the late afternoon.
Convection may largely remain on the cool side of the baroclinic
zone outside of the TX Trans-Pecos, but an increase in thunderstorm
coverage/intensity is anticipated by late afternoon to early
evening. Given the degree of shear along with moderate mid-level
lapse rates, isolated large hail should be the main hazard. Isolated
severe wind will probably be maximized during the early to
mid-evening near the front as consolidation into a larger convective
swath likely occurs. A tornado will also be possible in the Permian
Basin vicinity during the early evening where a brief overlap of
enlarging low-level hodographs should coincide with waning
surface-based instability. Overall severe threat will diminish
towards late evening given an increasing dearth of instability with
eastern extent.
..Grams/Bentley.. 11/06/2019
$$