JD:
00-153
DoW:
WED/THU
UTC
Date:
01JUNE2000
SUMMARY:
Sprites and Elves on
>50%
Positive Squall Line
TLE
PREDICTION:
[ 0.10] 0.2 chance of TLEs; 0.2 chance
of viewing
RESULTS:
12+ elves and
sprites
LESSONS:
Smoke Influenced Squall Line
PERSONNEL:
Nelson, Fossum, Nordem, Gerken,
STEPS
STATUS:
Operations. LMA operational.
Worked both storm to south as well as cell that develop to their
northwest.
YRFS OPERATION LOGS: The synoptic
situation changed radically after
the forecast was made.n Early evening saw a few scattered thunderstorms
on
the nose of a LLJ and inflow to a low which was situated in the NE
corner
of CO. Several moisture boundaries were evident in the surface plots
from
RAP/NCAR. Most of the cells developed along one of these boundaries
and
were supported by the low. About 0430Z, a cold front came through
the
area, which dramtically lowered the RH and increased the visibility
which
had been reduced due to smoke. In the NE panhandle, however, low
level
moist inflow along the right side of the low encountered the frontal
boundary. A squall line developed which eventually extended some
500km
from the NE/CO border southwest of Sidney, NE to south of Watertown,
SD.
This line had more support along the northern end and the southern end
in
NE dissipated at around 0730utc. Line was about 25-30 km wide along
the
southern half early in lifetime, and grew to about 50km near dissipation.
Lyons in Goodland for STEPS meeting. Extremely strong winds and
extreme
dewpoint gradients were noted in CO-KS area. Wind gust to 82 mph in
Burlington. Wind damage noted in Goodland. Perhaps due to gradient
flow?
Extremely strange. Lyons gets picture of cap busting over Ft. Morgan
with
extremely vertcauilly sdtreched turrets.
LLTV Obs began at 0257Z with red and blue cameras running. Just
lightning
obs over the steps/LMA domain for 2 hours (almost all -CGs). Camera
A
(blue) was switched to telephoto mode at 0340Z to look for any jets
from
the convection at 150-200 km east of YRFS.
At the start of tape 2, camera A (blue) was turned to the NE to view
convection in the NE panhandle. Sprites were observed from west of
Valentine starting at 0604. Between 0630 and 0730Z, a series of elves
were
observed from the northern extent near Winner, SD. Additional sprites
were
seen from the northern end by both YRFS and Stanford
instrumentation.
Photodiode tested, needs some slight adjustments.
Data Acq system trigger is now OK.
Obs ended at 0800 with a tear down in 40mph winds.
STEPS
OPERATIONS:
Full operations
KEY RESULTS :
Squall line with nearly
100% CGs produces TLEs……and smoke
is in the air from many wildfires. But why was small cell that formed
near
Ft. Morgan all negative. It may have been influenced by different
airmass.
Very careful surface analyses is required due to the strange frontal
boundary
interactions.
Total TLEs from Yucca Ridge This Campaign:
153
EQUIPMENT:
FMA
Red Xybion
(A)-Patrol:
1 tapes
Sony TRV900
3CCD:
in Goodland
JVC
KY-19:
shoot daytime TL/STEPS Cam
(to ESE);
Pulnix
CCD:
shoot various TL
scenes
Photodiode:
lens mated to original
unit, tested with strobe
Winckler
PMT:
available
GPS:
OK
WWV
Source:
OK
VLF
Inspire:
OK
ELF
N-S:
not
available
ELF
E-W:
not
available
NLDN
Live:
OK
NLDN
Paper:
12 maps
NLDN
Archive:
0 saves
MRC Data
Acquisition:
working on new trigger
FMA Data
Acquisition:
not
available
Thunder
Mic:
available
LANL
Tracker:
OK
Red Xybion
(B)-Zoom;
1 tapes
Red Xybion
(C)-Tele:
0 tapes
Blue
Xybion(D)-zoom:
1 tapes
Mountain
Cam:
nominal
STEPS
Cam:
nominal
Shure
Mic:
OK
NEXRAD
Archive:
OK-revised scrips
GOES
Archive:
OK-revised scrips
RUC2
Archive:
OK
STANFORD/STAR LAB:
Telescope
OK
LLTV
OK
ELF/VLF
OK
UTAH STATE UNIVERSITY: not
present
MIT
ELF:
problems with vertical
antenna, Vadim working on problem
FUELLEKRUG
ELF:
says 80% operational
ISRAELI
ELF:
nominal
Walter A. Lyons, Ph.D.,
CCM
walyons@frii.com
Yucca Ridge Field
Station
970-568-7664 (voice)
46050 Weld County Road
13
970-482-8627 (fax)
Fort COllins, CO
80524
970-690-0422 (PCS)