Flight Number: 970209H1 Page 1 of
Date: February 9, 1997 Aircraft ID: 42RF Scientist: Jorgensen
Event Log
Time Approx. Location Event & Comments
(UTC) (Lat, Lon)
13:00:59 Shannon Engine Start. This is Flight 8 IOP12 on Low 34a near
58N 24W. Coordinated with UK C-130 and NCAR Electra
13:04:31 Shannon Block out
13:13:20 take off
13:21:57 52.938 -9.450 Radar system up - TA looks fine
13:24:32 53.057 -9.640 heavy overcast skies here, sea looks calm below-flight
level winds are 225 at 42 knots (600 mb)-still in
climb out to our ferry altitude of 16k ft.
13:28:10 53.237 -9.909 radar recording up
13:32:27 53.451 -10.238 seeing tiny ice particles on PMS radar return less
than 0 although getting some coherent velocity
structure
13:44:45 54.050 -11.388 still in ice particles, but RH is about 10% - curious?
13:52:24 54.438 -12.065 contact with METMAn60
13:54:24 54.558 -12.211 out in the clear now-no echo and sun is out - broken
cu flield below-some whictcaps on the sea below
13:59:42 54.854 -12.636 sevarl contrails to our SW heading NW parallel to our
track
14:02:32 55.011 -12.877 begin descent to 5k ft-70 nm from buoy
14:07:17 55.309 -13.279 lots of whitecaps on the sea sfc below
14:11:25 55.557 -13.578 at 5k ft RA- in cu field 30 nm from buoy about 6 min
to go
14:19:37 55.974 -14.206 over buoy turn to trk to pt 1 (57 22N 19 53W ETA 1512
UTC
14:22:13 56.058 -14.475 some echoes on LF 100-150 nm ahead short band segments
50 nm lone oriented SE to NW
14:26:14 56.176 -14.885 slowing down to about 225 kts GS to arrive at pt 1
about the same time as METMAN
14:30:19 Contact with METMAN-their ETA to IP (pt. A) is 1538.
Our ETA to pt. 1 is now 1520-we'll start our run and
let METMAN catch up
14:38:33 56.477 -16.027 going through a small band of convective looking
precip on TA
14:40:19 56.519 -16.185 out of the echoes
14:43:33 56.601 -16.499 more north-south oriented bands100-150 nm ahead
14:49:35 56.758 -17.114 may be the cold front ahead about 120 nm along about
20.5W longitude
14:57:02 56.928 -17.818 going into a field of stratiform echo, with a few
embedded convctive cells
15:05:45 57.125 -18.671 in fairly extensive stratiform precip now
15:09:02 57.195 -19.008 sft winds now up to 175/71 kts-interesting sloped
structure on the TA aft scan, sloping down from south
to north
15:12:16 57.266 -19.339 speeding back up as extensive precip field ahead means
perls
15:15:09 57.333 -19.667 big bumps apparently going through the cold front.
Winds are still 173/70 knts
15:16:29 57.372 -19.825 at pt. 1-doing a perl #1 to the right in extensive
stratiform precip
15:19:34 57.430 -19.881 end of perl #1 - start leg 1 trk 291 to pt. 2
15:26:54 57.669 -20.762 strong bright band-apparently a circular echo free
region on the LF aoubt 80 nm to our wsw - cyclone
center?
15:31:05 57.846 -21.261 start perl #2 in heavy stratiform apparently 80 nm NE
of cyclone center
15:31:46 cyclone center marked by curved rainbands along the
east, north, and western sides
15:34:14 end of perl #2 - resume 294 trk.
15:42:43 58.191 -22.390 "hook" appendage indicative of cyclone center well
marked on LF about 80 nm to our WSW.
15:44:59 58.276 -22.668 begin perl #3 in heavy stratiform precip north of
cyclone center.
15:48:26 end of perl #3 - resume 296 trk
15:59:04 58.648 -24.045 start of perl #4 in extensive stratiform precip
16:01:15 58.717 -24.024 end of perl #4 resume original track
16:01:50 METMAN reports e-mail from Ops Center that indicates
low center to be somewhat south of our forecasted
track at mid-day by perhaps 60 nm
16:05:59 METMAN reports from Ops Center that the Electra will
not fly due to problems today
16:10:08 58.964 -25.132 start perl #5 in moderate stratiform precip
16:10:34 thinking about modifing the flight plan to continue
working the cyclone center instead of moving to the
cold front after the completion of leg 2
16:14:31 End of perl #5, resume track
16:14:47 METMAN reports sonde troubles
16:15:48 59.066 -25.475 dramatic wind shift winds now 043/14 knots sfc press
964
16:25:37 59.359 -26.519 entering perl #6
back to original track eta to pt 2 1634 UTC
16:33:37 59.500 -27.133 end of leg 1 entering perl #7 before track to pt 3
16:45:48 58.890 -27.583 at pt 3 entering perl #7 prior to starting leg 2
16:49:51 end of perl # 7 start leg 2
17:00:09 58.764 -26.351 start perl #8 in light stratiform precip on the west
side of the cyclone
17:10:06 58.680 -25.466 start perl #9 in light stratiform precip
17:20:11 58.615 -24.611 start perl #10 in moderate stratiform precip on west
side of cyclone
17:20:46 LF sees a band of 30 dBZ precip 100 miles ahead - bent
back front?
17:29:49 58.504 -23.858 some turbulence as we crash through the "bent back"
band on the west side of the cyclone
17:31:02 58.491 -23.704 wild slopes to the contours on the TA
17:32:09 58.495 -23.592 start perl #11 just to east of the west band virtually
out of precip
17:34:54 end perl #11
17:35:14 58.500 -23.597 sfc pressure now 953 mb!!
17:37:20 58.468 -23.369 many convective type cells on this side of the band
17:38:32 58.451 -23.230 can see the sea sfc below
17:40:25 58.427 -23.006 big whitecaps below
17:40:43 have worked out coordinates for two more runs thought
the cyclone using the same center motion and speed.
For P-3 these points are: pt 5: 57.1N 20W, pt 6: 59.2N
27.5W, pt 7: 58 40N 27 50W, and pt. 8: 57 35N 19 40W
17:50:26 58.280 -21.882 cutting this leg short to save some time, proceeding
to new pt 5 at 57 40N, 22 05W
17:59:48 57.836 -21.993 good view on LF of cold front, warm front to north,
and bent back front to west of cyclone
18:01:54 57.732 -22.028 entering precip at our new pt 5 turn to track to pt.6
start of leg 3
18:04:03 METMAN reports only about a 30-40% sonde success rate
18:04:49 57.776 -22.287 precip to our left as we proceed to new pt 6
18:12:46 57.976 -23.004 back into stratiform precip now
18:20:30 58.197 -23.719 curved band on LF aout 15 nm to the north suggests we
are now south of the cyclone center by about 50--60 nm
18:21:32 diameter of cloud free region near the center is about
50 nm
18:22:11 58.241 -23.877 stll in light to moderate stratiform precip
18:36:33 58.539 -25.214 sfc pressure now 957 mb south of the cyclone
18:41:14 58.653 -25.654 radar data system locked up for a few minutes
18:42:10 58.675 -25.739 winds are now going northwesterly here on the SW side
of the cyclone
18:44:56 58.743 -26.004 stratiform precip is a bit heavier now
18:51:15 58.902 -26.636 end of leg 3. Turn to track to new pt. 7 at 58 35N 277
00W
18:52:25 went far enough west to get into the northerly flow
18:56:06 58.604 -26.912 at new pt. 7, turn to track 95 to pt. 8
18:56:46 radar recording back up at 1853
18:58:51 58.574 -26.588 rather shallow stratiform precip (2 km tops) on TA
18:59:25 we're running about 1.5 hours ahead of METMAN because
we cut off our last eastbound leg to save time
19:25:50 58.162 -23.029 some turbulence. TA shows light stratiform precip
19:38:47 57.898 -21.258 out of the precip - can see the moon off to the west
19:40:35 57.859 -21.015 choppy turbulence as we proceed ESE to pt 8 (57 35N,
19 40W) ETA about 9 minutes
19:42:25 57.821 -20.769 Pilot reports northern lights can be seen to our NNE
19:43:18 57.801 -20.653 convective rainband can be seen 100-150 nm to the NE
on LF oriented NW to SE - cold frontal bands?
19:50:30 57.640 -19.704 at pt. 8 - end of leg 4, turn to track to the buoy
(118 degrees). ETA 2038
19:53:01 57.555 -19.405 looks like the buoy is just on the other side of the
cold frontal rainband 200 nm ahead
19:59:10 57.344 -18.707 nice view of the northern lights arcing over the top
of the aircraft from north to south
19:59:56 57.319 -18.620 flying though a field of cold air convective cells.
Must be flying near the tops as turbulence is going up
20:00:55 57.289 -18.515 nice shot on LF of cold frontal rainbands 199 nm to
our east
20:02:39 57.233 -18.321 passing just to the right of a convective cell with 45
dBZ reflectivity cores
20:17:02 56.803 -16.748 buoy appears to now be under the frontal rainband
about 100 nm ahead
20:29:19 56.399 -15.460 approaching cold frontal band-going into stratiform
precip now
20:30:38 56.350 -15.310 nice view on LF of narrow cold frontal rainbands (two
about parallel, spaced by 10 nm) about 40 nm ahead.
Narrow region of 40 dBZ max in earnmost band
20:33:34 56.243 -14.991 in more intense stratiform precip now
20:41:12 55.985 -14.201 at buoy, executing perl #12 over buoy in stratiform
precip about 10 nm behind (to the west) of the line
20:44:37 55.985 -14.129 end of perl #12 start of southbound leg
20:46:38 correcting a bit to the east to bring the band to
within about 5 nm of us
20:47:04 max dBZ about 45, as intense as we've seen in FASTEX
so far
20:53:26 radar system froze up at 2052
20:59:42 55.244 -13.759 TA back up. Flying parallel to the line about 10 nm
hehind it. TRK 180
21:10:04 54.718 -13.417 center of narrow cold frontal band now 10 km to the
left
21:11:51 54.625 -13.423 good position now relative to band maximum dBZ
21:12:53 cold frontal band width about 3 km
21:23:31 54.051 -13.520 apparently at the end of the line on NO radar-
continue to trk 180
21:32:38 53.592 -13.613 passing by nice cells
21:33:48 having to jog eastward a couple of times to clear cells
21:38:18 53.305 -13.596 broke through the line as it shifted its orientation
back to the east
21:43:37 53.020 -13.574 at end of southern run, turn to track to SNN and climb
out to 10k ft
21:54:53 52.985 -12.041 still embedded in farly heavy stratiform precip - well
defined bright band ~1 km below
22:10:08 52.815 -9.929 begin descent in SNN
22:42:01 land
22:48:02 Block In