20 July 1995 -- MCS Anvil Growth
GOES-8 Water Vapor Winds

Upper-tropospheric water vapor winds were calculated using 15-minute GOES-8 IR channel 3 (water vapor) imager data during the development of a Mesoscale Convective System over the central Plains region on 19-20 July 1995. Wind vectors at their various assigned height levels were used in combination with time-interpolated "guess" wind analyses from the NCEP AVN model to construct gridded wind analyses. The winds from these grids were then used to evaluate divergence at 200 hPa (near the average height of the wind vectors). These water vapor winds provide a relatively consistent and continuous picture of the upper-level flow in the vicinity of the convective complex.

Early Stage | Mature Stage | Decay Stage | Animations

Early Stage of MCS Development

GOES-8 water vapor winds

23:02 UTC 19 July 1995 -- Water vapor winds, Divergence

During the early stages of MCS development (23:00-02:00 UTC), maximum wind divergence values ranged from 45-55 x 10-5 s-1 over eastern Nebraska and northern Kansas, generally aligned with the cirrus cloud sheild.

Mature Stage of MCS -- Maximum Divergence Aloft

GOES-8 water vapor winds

04:15 UTC 20 July 1995 -- Water vapor winds, Divergence

The MCS was mature with respect to deep convection from about 02:00-05:00 UTC. The maximum divergence aloft (indicative of the region of strongest upward vertical motion) occurred between 04:00 and 05:00 UTC, with values of 70-80 x 10-5 s-1 over northcentral Kansas. Note the preferred expansion of the cirrus cloud shield to the southeast (to the right of the ambient southwesterly flow).

Decay Stage of MCS -- Rapid Decline of Divergence Aloft

GOES-8 water vapor winds

11:02 UTC 20 July 1995 -- Water vapor winds, Divergence

The MCS began to decay from about 05:00 to 08:00 UTC. There is a rapid decrease in the storm-top divergence after 05:30 UTC, with values remaining between 50-60 x 10-5 s-1 over eastern Kansas. Maximum divergence values appeared to migrate to the rear (southwestern) portion of the MCS during the final hours.

Image animation at 30-minute intervals (23:00 UTC 19 July to 13:00 UTC 20 July):

Java | QuickTime

Back to the Forecasting Applications index