1 APRIL 1998
During the 1st week of April, no operations took place
as the set-up of the project was being completed.
8 APRIL 1998
Forecast: No forecast was available for this day, however, after
watching convective events unfold across west Texas, a decision was
made to operate the ADRAD. By later in the afternoon, a forecast
was made for convection to occur over the gulf on the 9th,
which would be ideal for a first ferry flight for the ER-2.
Operations: The ADRAD was operated from 0900 to 1300 UTC on the
morning of the 8th to capture a developing squall line out
west. The TRMM overpass scheduled at 1200 across the region was not able
to capture the mature asymmetric squall line, because the system began to
weaken considerably by 1100 UTC.
Side Notes: Field installation of the NASA raingauge network began,
and both the NOAA AL Profiler and ETL X-Polimetric radar were operational
as well. The TAMU van and truck were being retrofitted with sounding
equipment.
9 APRIL 1998
Forecast: No significant chance for convection until 4/12.
Operations: The ER-2 completed the ferry flight over the gulf
for calibration purposes. The flight was from Dryden to Eglin AFB
landing at 1730 UTC. Useful calibration data over the water was
obtained for EDOP and AMPR.
Side Notes: The remaining of 12 raingauges for the surface network
was installed along with the 6 APL Disdrometers.
Also, the Joss
disdromter was placed in close proximity with one of the APL disdrometers
at the Profiler site.
10 APRIL 1998
Forecast: No precipitation was expected until the 12th.
After which, the long-range forecast was for the chance of convection
within the domain for the next few days.
Operations: An alert was scheduled for an ER-2 flight Sunday
evening/night (4/12).
Special soundings from fellow NWS offices were not requested.
11 APRIL 1998
Forecast: Convection was expected to fire late in the day across
north-central Texas with the precipitation area expanding into the
region as a front/dryline approached the Texas coast. Precipitation
was still forecasted to occur across the domain through the next
couple of days.
Operations:The decision was made to cancel
the ER-2 flight Sunday night, with possible activation on Monday
night (4/13) at 0000 UTC.
Side Notes: All surface based systems were ready for operations
as well as the mobile sounding vehicles. One vehicle was sent to
HGX while the other stayed at TAMU. All sounding and radar crews
were also scheduled.
13 APRIL 1998
Forecast: The cap was still in place across south and central Texas,
which would confine the convection off to the north. A convective
possibility existed along the front farther east on the
14th, in the Lake Charles region. The extended forecast has
area still capped.
Operations: The early alert for operations at 0000 UTC (4/13)
was changed for takeoff at 0000 UTC 15 April due to the failed
development of convection and the chaotic winds over at Eglin AFB.
Side Notes: The Lear jet was expected to arrive into Texas on
the 14th of April.
14 APRIL 1998
Forecast: No organized long-lived precipitation was expected across Texas.
Other areas of organized convection would continue along a stationary front
in Alabama and Georgia. Parameters were coming together for a convective
event over Texas on the 16th.
Operations: There was an ER-2 flight planned for 0000 UTC around
central Georgia. X-Pol operated the night before to collect data on
drizzle in the Houston area. Another flight was scheduled for Thursday
(4/16) as tomorrow was declared a down day due to forecast. The flight
over Georgia was a success as all aircraft instruments operated superbly,
including the EDOP and AMPR, which collected good data. A calibration
check was also performed over the Gulf of Mexico.
15 APRIL 1998
Forecast: Convection continued to fire across north Texas along an
old outflow boundary and more was expected to develop along the dryline
in central Texas.
A slight possibility existed for squall line development and propagation
into the area, but there was more confidence in the forecast for
convection on Thursday (4/16).
Operations: Declared a down day due to lack of expected precipitation,
and for preparations of tomorrow's flight around 1800. The ADRAD was
operated to check various calibrations and settings including a check
of the antenna controller after a design flaw was corrected.
16 APRIL 1998
Forecast: Uncertainty existed in whether the cap would weaken enough
to allow convective development along the front in southeast Texas
and Louisiana. Morning soundings taken at CLL and HGX showed the
cap stronger than anticipated.
Operations: The scheduled flight was cancelled due to atmospheric
trends. Low ceilings and unfavorable winds prevented take-off at Eglin
for the ER-2. X-Pol continued to operate since convection was still
possible around Houston. A flight was scheduled for the 17th
at 0300.
Side Notes: The Lear jet arrived into College Station at 0000 UTC
and all systems checked out. The ADRAD's antenna controller problem
was fixed and ready to operate.
17 APRIL 1998
Forecast: Widespread convection was expected to develop over the
coast along a cold front as an upper level trough swung through the
region from old Mexico beginning later in the night and throughout the
day Saturday (4/18).
Operations: Alert time was scheduled for the ER-2 flight around 0300,
but was later cancelled due to low ceilings at Eglin. Special soundings
were launched later in the night at CLL, HGX, CRP, and LCH. A test flight
for the Lear was planned for 1830. The ER-2 was put on alert for 1600
UTC tomorrow for the Lake Charles area. The X-Pol operated the entire
night and through the day Saturday.
Side Notes: The ADRAD was labeled down until Monday, as some wires
and a relay burned up in the antenna controller circuitry.
Also, several sounding launches failed at HGX during 2100 to 2330 UTC.
18 APRIL 1998
Forecast: Convection to continue across domain.
Operations: A SW-NE band of weak convection and stratiform rain
continued half way between CLL and HOU.
NEXRAD showed a strip of 50 dBZ values most of the night. Most of the
activity was north of the recently installed raingauge network around
Houston early on, but later moved over all of Houston before exiting
the area. The TRMM overpass paralleled the activity but was too far
south to obtain ideal measurements, although the TMI swath at 1807
was within range. X-Pol operated continuously from 1830 on the 17th
to 2030 on the 18th.
The ER-2 flight lasted from 1630 to
2115 UTC with the path over both the profiler and x-pol radar sites.
The Lear flight flew from 1753 to 2005 UTC. Other soundings were
launched north of the system and within the system from the TAMU van.
The aircraft were able to connect for a common flight from
the southeast to the northwest along a line at these points. A: 28.42' N
94.15' W to B: 30.26'N 96.00' W.
Later, the ER-2 branched off onto another line from C: 29.45'N 95.30 W
to D: 29.19'N 93.08' W. Good data was collected by the XPOL, the
Profiler, the Lear CPI, EDOP, AMPR, and LIP.
19/20 APRIL 1998
Forecast: No precipitation expected today, but possibility exists for
light precip on Monday (4/20).
Operations: None commenced. A plan for a calibration check over the
gulf on the 20th with
the ER-2 and TRMM satellite was discussed.
21 APRIL 1998
Forecast: Convective and stratiform event will continue north of the
area in Texas.
Operations: Initial planned calibration check over the gulf was
changed to a coordinated flight with the TRMM overpass north of TAMU.
The AMPR contained good data, while the EDOP and LIP failed.
The flight consisted of 2 legs across and along the line, which lasted
from 0330 to 0915 UTC.
Mobile soundings were taken southeast of the band, which was oriented
from WSW to ENE across northern Texas.
22/23/24 APRIL 1998
Forecast: No precipitation expected until Sunday (4/26).
Operations: The ER-2 flight was planned for coordination with the
TRMM overpass for calibration purposes at 0200 on the 23rd
over the east Gulf of Mexico. AMPR collected good data,
but the EDOP and LIP failed under clear sky conditions.
25 APRIL 1998
Forecast: Moisture did not return in time to cause convection
south of the Red River, therefore nothing was expected in the area.
However, better-organized precipitation was possible on Sunday.
Operations: Previous tentative alert for operations was cancelled
due to updated forecast. Plans were made for additional soundings at
1700 tomorrow and flight takeoff at 2330 UTC.
All other platforms were put on alert for late Sunday.
Side Notes: TAMU truck was delivered back to HGX after improving
the antenna reception.
26 APRIL 1998
Forecast: A surface trough forming NW-SE across central Texas was
the focus for convective development in the afternoon as instability
continued to increase. Widespread deep convection was then progged
to move eastward overnight, mainly north of CLL.
Operations: A mobile sounding was taken near Austin at 1700 for
forecast purposes, while others were taken during the convective event.
FTW special sounding was also taken at 1700.
ER-2 took off at 2330
but aborted the flight early on due to tremendous turbulence from the
storms NW of CLL. The EDOP and MAMS instrumentation were accidentally
turned off during the first flight line, while strong electrical activity
was observed with the LIP. The Lear aborted flight take off due to
low ceilings. The ADRAD began collecting data at 2100 UTC.
Communication problems were noted between the ADRAD base station
and the ER-2.
27 APRIL 1998
Forecast: Elevated convection was noted north of slow moving cold
front near CLL-CRP.
The area was expected to intensify and continue moving eastward
eventually passing through Houston and Louisiana later in the night.
Operations: Previous alert for ER-2 was cancelled due to right roll
spoiler failure. ADRAD continued operations from the night before to
0500 4/28. The X-POL took good data as well. Both radars collected
data during the 0300 overpass time. The Lear took off at 1610 through
1805 to look at dissipating convection NE of CLL.
Later that night,
the jet flew again from 0210 to 0400 UTC to work the TRMM overpass in
a convection and stratiform region 60 miles ENE of CLL. Lightning
damaged the 2nd transmitter on the plane.
CLL and HGX special soundings were taken at 1700, as well as other
mobile soundings throughout the event from the TAMU van. Houston took
additional soundings at 0000 and 0300 4/28 with additional sonde
problems noted.
28 APRIL 1998
Forecast: Nothing significant was expected across the Texas area, but a
squall line was progged to form just east of Lake Charles in the
afternoon with the front possibly affecting Eglin.
Operations: The ER-2 flight was cancelled and put on standby for
2200 4/29. The Lear took off at 0542 4/29 to target stratiform region
near LA coast and to coordinate with TRMM overpass at 0634. X-POL
collected data from the Houston area.
ADRAD operated from 0000 to 0700. A special sounding was taken by
LCH at 0600.
Side Notes: The ER-2 spoiler problem was determined to be an
intermittent broken wire.
The Lear transmitter was repaired and operational during flight.
29 APRIL 1998
Forecast: Deep convection would continue along stationary front
in the Gulf and propagate eastward. Nothing was expected over Texas
for awhile.
Operations: Plans were made to alert ER-2 and Lear for a coordinated
flight over the Gulf tomorrow night (4/30).
30 APRIL 1998
Forecast: Convection will continue across the southeastern US in the
vicinity of Eglin, Alabama, and Georgia. A squall line should develop
across N. Alabama and Georgia and move eastward.
Operations: The ER-2 and Lear jet rendezvoused over the southeast
from 0000 to 0215 UTC to coordinate with the TRMM overpass at 0057.
They flew along the back edge of a mature MCS in the convective and
stratiform regions. The ER-2 was able to capture the 0411 overpass
as well. During the flight, strong electrical activity was noted as
a lightning strike knocked out the new radio and caused an engine
problem in the Lear. The ER-2 reported EDOP and LIP failure once
again. Strong cells were captured with the AMPR and MIR, while the
first MTS data of the project was collected.
1 MAY 1998
Forecast: Only isolated convection was expected across the
northeastern Gulf coastal plain, otherwise convective development
would occur along a southward moving cold front in Texas by tomorrow
afternoon (5/2).
Operations: Plan for a flight tomorrow night. ER-2 alert for
takeoff was at 0600 and at 0700 UTC 5/3 for the Lear.
2/3 MAY 1998
Forecast: Front would continue to push offshore and stall in the
northern Gulf. Convective activity should continue in the Gulf and
in the southeastern US.
Operations: Flight's were cancelled due to lack of the system over
Texas not maturing. The ADARD operated from 2100 to 1000 UTC to capture
the evolution of the developing storms. TAMU sounding van launched at
0000 and 0500 Saturday evening (5/3). HGX special soundings were also
launched Saturday evening.
Side Notes: The MAMS instruments were replaced by the SLS on the
ER-2.
4 MAY 1998
Forecast: With a front stalled across the southern area near Houston,
convective development was possible over the region along the front. Also,
more convection was expected over the southeast near Eglin.
Operations: Good coordination was obtained with the TRMM overpass at 2146.
EDOP, AMPR, LIP, and MIR all collected good data. Strong electrical activity
was observed with the squall line and most of the stratiform region was over
Southern Florida.
6 MAY 1998
Forecast: The cap would continue for Texas while convection fired over
from Kansas to Arkansas. Other convection would continue in the Midwest
and in the southeastern US.
Operations: A joint flight was attempted with the Lear and ER-2 over
Florida at 1820 UTC for a convective system along the MS/AL coastline.
Communication was disrupted between the two causing a missed event for
the ER-2, which returned to Dryden AFB. The Lear jet flew an additional
flight over the same area near Mobile from 2135 to 2247 to gather more
cloud physics data before refueling and returning to CLL.
8 MAY 1998
Forecast: Supercellular convection was expected across NW Texas
along a warm front/dryline interaction by afternoon. With time, cells
were expected to evolve into a squall line system and propagate eastward.
Operations: The TAMU sounding van launched several sondes in NW Texas.
The ADRAD began collecting data from 0300 to 0900 UTC (5/9). The Lear jet
penetrated a supercell anvil at 2351 to 0111 before aborting the mission.
TEFLUN Data Category
TEFLUN Data 