SPC AC 260500

   Day 2 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   1100 PM CST Thu Nov 25 2021

   Valid 271200Z - 281200Z

   ...NO THUNDERSTORM AREAS FORECAST...

   ...SUMMARY...
   The risk for thunderstorms appears negligible across the U.S.
   Saturday through Saturday night.

   ...Discussion...
   One branch of westerlies emanating from the mid-latitude Pacific
   appears likely to remain fairly amplified into and through this
   period.  This is forecast to include large-scale ridging across and
   inland of the Pacific coast, which may continue to build
   northeastward across the Canadian Prairies and parts of the northern
   U.S. Great Plains.  Downstream, models indicate that broad and deep
   mid-level troughing will persist, with a couple of short wave
   perturbations digging to the lee of the ridging, in the wake of a
   more substantive mid-level wave and embedded low forecast to turn
   north-northeast of the northern New England coast.  Near the
   surface, it appears that this will include a deep, occluding cyclone
   migrating across the lower St. Lawrence Valley into southeastern
   Quebec.  

   It appears that a frontal zone trailing the occluding cyclone will
   stall across the Gulf of Mexico, south of the Florida Peninsula into
   areas southeast and south of the lower Rio Grande Valley.  This is
   forecast to occur in response to the northeastward and eastward
   acceleration of the remnants of a cut-off low currently digging into
   northern portions of Baja California Sur.

   Models do indicate that mid/upper forcing for ascent, coupled with
   elevated moisture return across the lower Rio Grande Valley through
   central Texas, may contribute to an expansive shield of light
   precipitation with embedded convection across much of Texas into
   adjacent portions of the lower Mississippi Valley Saturday through
   Saturday night.  While latest NAM forecast soundings suggest that it
   might not be out of the question that some of this activity might be
   able to generate sporadic/occasional lightning, probabilities are
   still being maintained at less than 10 percent due to generally weak
   lapse rates and weak/unfocused low-level forcing for large-scale
   ascent.

   ..Kerr.. 11/26/2021

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   NOTE: THE NEXT DAY 2 OUTLOOK IS SCHEDULED BY 1730Z