Severe Storm Risk - Panama City Beach, FL

• Severe Storm Risk

  Fri 08:00 AM - Sat 07:00 AM

  There is a Marginal Severe Storm Risk for your location. Continue reading for today's outlook from the National Weather Service's Storm Prediction Center. -------------------- National Severe Storm Outlook THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM MIDDLE TENNESSEE TO THE FLORIDA PANHANDLE SUMMARY A marginal tornado threat is expected to develop this morning and afternoon across parts of Alabama, western Georgia and middle Tennessee. Isolated damaging to severe gusts will be possible in parts of Alabama, southwest Georgia and the Florida Panhandle. Synopsis In mid/upper levels, the CONUS portion of the large-scale pattern this period will be characterized by a "dirty" Rex block in the East, and troughing in the West. The block will be composed of an anticyclone drifting eastward over the Upper Great Lakes, and a small, deep-layer cyclone -- resulting from the merger of a weak, midlatitude, mid/upper-tropospheric low with the low/middle-level remnants of post-tropical cyclone Francine -- centered currently near BVX. This low should weaken gradually and meander slowly over the Mid-South, possibly drifting east-southeastward back across the MEM area through the period, but with negligible movement on the synoptic scale. In the northern stream, a mid/upper-level cyclone -- evident in moisture-channel imagery over southern SK -- will eject northeastward to northern MB and devolve to an open-wave trough by 12Z tomorrow. In its wake, broadly cyclonic flow aloft, with mostly minor embedded shortwaves/vorticity maxima -- will cover the northwestern 1/4 of the CONUS. To its east, midlevel DCVA/ascent from a weak trough trailing the cyclone, combined with low-level warm advection and gradual moistening, will support general thunder potential over portions of the northern Plains to upper Mississippi Valley. At the surface, 11Z analysis showed a wavy, quasistationary to warm front extending from off the SC Coast across southern GA and eastern/northern AL, intersecting a weak cold front there, then as an occluded front into the low over AR. This boundary should drift diffusely northward through the period, while weakening. A stationary to slow cold front was drawn from southern MB across central ND and western SD, and should drift eastward over the central Dakotas today through tonight. Southeast Isolated, mostly short-lived supercells will be possible today, mainly in a belt of low-level convergence from parts of central/ eastern AL and western GA into the Tennessee Valley, with a marginal tornado threat. Farther south, in weaker shear (but greater instability), a few of the stronger cells or small clusters may produce damaging gusts. A corridor of relatively maximized low-level shear/SRH remains near the old, diffuse warm-frontal zone well southeast of the center of Francine's remnants. Both that and a moisture/buoyancy axis to its west (centered roughly over the axis of the outlooked corridor) should move little today, given the slow filling and lack of motion of the related deep-layer cyclone over the Mid-South. Rich low- level moisture will persist in this corridor, with surface dewpoints commonly in the 70s F, and low LCLs. Weaknesses of both surface winds and midlevel flow will sandwich a 35-40-kt east-southeasterly to southeasterly LLJ that keeps hodographs somewhat enlarged and effective SRH in the 150-300 J/kg range over eastern/northern AL into southern mid TN. With some localized help from boundaries (outflow or differential-heating), a brief tornado is possible. A few of the most vigorous, water-loaded downdrafts will be capable of localized strong to marginally severe gusts, especially over southern areas where peak MLCAPE may reach about 2000 J/kg. Activity generally should weaken this evening and overnight as the airmass stabilizes and the remnants of Francine continue to decay.