Weather Forecasts

Daily Weather Summary

June 28, 1999:

Air mass over Tennessee very moist, and with some sunshine this morning, it has also become unstable. There is also fairly strong wind shear in the PBL, with winds at the surface out of the S at 15 kts, with winds up at 950 mb out of the west at 25 kts (per 12Z BNA sounding). As upper level shortwaves approach from the NW, and a frontal boundary moves closer, expect a few thunderstorms this afternoon and overnight. High: 84 Low: 74 Mixing Hgt: around 900 m.

Tomorrow's Forecast

June 28, 1999:

Frontal boundary moves into area, so some showers still around in the morning, but as drier air moves in from the north, expect much lower rain chances by Tuesday afternoon, with clouds decreasing some. 850 mb winds back off to 10-15 kts by late Tuesday afternoon, out of the NW. High: 86 Low: 67

Day after Tomorrow Forecast

June 29, 1999:

Frontal boundary moves back northward into Tennessee on Wednesday, so with added moisture and another 500 mb shortwave approaching, chances for mainly afternoon and evening thunderstorms return. High: 88 Low: 70

Outlook

Bermuda high finally tries to build back in, but still expect scattered afternoon and evening thunderstorms each day, with temperatures warming up some. Highs: 90-95. Lows: 70-75.

Profiler Plume Depiction

The following shows a depiction of plume locations as predicted by the profiler winds assimilated into a one-dimensional boundary layer model. The top image shows particle positions as of the previous evening. The lower image shows particle positions as of the following morning for particles released beginning the previous noon.

Forecast Plumes

The following gives a depiction of plume locations using a Lagranagian Particle Model coupled to the Regional Spectral Model. The RSM is run daily in a forecast mode at TVA Muscle Shoals, Alabama.

Plume based on 00z initial fields (mpg file optimized for QuickTime)

Plume based on 12z initial fields (mpg file optimized for QuickTime)

ARL Hysplit Trajectories

Nashville Soundings