SPRITES 99 YUCCA RIDGE FIELD STATION
FMA Research


JD 99223 11 AUGUST 1999
PRELIMINARY SPRITE LOG

The following is a very preliminary listing of the times of sprites imaged at the Yucca Ridge Field Station. These are based solely on real-time visual inspection of the video monitoring system. There are most likely some additional sprites not listed and not all those below may in fact be sprites. All times are UTC. Times are likely to be within ±5 seconds of actual time.



SUMMARY: Massive MCC forms in northeast Colorado and tracks slowly due east during night through Nebraska. An F0 tornado spun up literally on top of the Yucca Ridge building (only minor damage) at 2325Z. Flash rates in the MC were sustained >6000/hr. The positive CG rate was very high (>40%) during the pre-sunset stages of the system, but steadily declined during the night, to as low as 3-4% after 0700Z. A massive stratiform shield did have many +CGs however, and these produced a number of sprites.

An especially interesting event was a dancer at 0907Z which was associated with a long string of +CGs near the MCC radar bright band.

UofA: Jelm was clouded in, Custer saw a few sprites before being clouded out. The balloon mission was scrubbed due to local winds. The MM5 forecast run ran without problems.

Total TLEs This Campaign: 1592


(S) = Sprite;  (E) = Elve;  (B) = Blue Jet;  (CF/CG) = Cloud/Ground flash;  (M)=Meteor

JD 99223 11 AUGUST 1999
0230 Start LLTV Observations
0248.55 [S-]
0258.10 [S-]
0310.15 [S-]
0314.29 [S-]
0323.XX [S-]
0329.21 [S]
0337.52 [S-]
0726.12 [S]
0726.14 [S]
0735.40 [S-]
0751.18 [S]
0758.50 [S]
0803.46 [S]
0809.54 [S]
0827.54 [S]
0834.06 [S]
0841.10 [S]
0907.25 [S]
0912.07 [S]
0914.35 [S]
0930 End LLTV Observations