P-3 Chief Scientist Event/Radar Log

 

Flight Number: 011215H

 

IMPROVE-II Flight #6

Date:  December 15, 2001      Aircraft ID: N42RF 

Chief Scientist: Bond

            ---------------------------------------------------------------------------------------------------

            Doppler Scientist: Grimit     Radar Tech: McMillan

          Cloud Physics Sci: XXX  Data Tech: XXX

          Radar parameters:         PRF1=PRF2 =1600, 0.50 microsecond pulse

                                      Setup file = IMPR1

                                      Pulses/sample = 32

                                      Threshold on REF

                                      Alternate Setup = IMPR2

          Mission Description:

          Scientific Crew: Nick Bond (PI), Eric Grimit (radar), ??? (cloud physics)

          AOC Crew: Taggart (P), Halverson (P), Wade (FE), Damiano (FD), Newman (N), Rogers (tech), Lynch (data), McNamara (tech), Delgado (dropsonde)

           

 

Event Log

Time (Lat, Lon), Track (deg), Static Pressure (mb), Radar Alt (m)

Event & Comments

220528 Z (47.70618, -122.59233).2 mb, 2309.0 m

Heading for Pt. A after 2159 takeoff

220917 Z (47.51405, -122.71321) 207.083°, 667.4 mb, 3156.0 m

Near cloud top

221344 Z (47.30615, -122.91550) 215.731°, 574.0 mb, 4399.0 m

2D probes turned on; in clear air

223953 Z (45.42513, -122.97736) 176.836°, 573.0 mb, 4478.0 m

Begin descent to Pt. A

225359 Z (44.50285, -123.03435) 179.094°, 812.0 mb, 1716.0 m

About halfway between Pt. A and Pt. F; breaks in pcp to W; more solid cellular pcp to E; cld phys shows droplets

225908 Z (44.17738, -123.03098) 181.462°, 811.9 mb, 1555.0 m

Aft scan shows higher echoes to W of cellular variety between 20 and 40 km

230529 Z (43.78178, -123.02838) 154.401°, 808.9 mb, 1648.0 m

Pt. F; never broke out of pcp completely as was expected; heaviest pcp just to the E during later part of the A-F leg

231255 Z (43.96243, -122.56686) .868°, 752.5 mb, 1972.0 m

Beginning of G-B leg; both aft and fore scans show 20-25 dBz cells less than 20 km to W; rest of pcp is very shallow associated with low-level drizzle

232323 Z (44.65295, -122.56152) .496°, 752.8 mb, 1507.0 m

Back into "cloud sandwich", upper lvl cld not feeding low lvl cld.  Radar echo is more scattered to the E now.

232552 Z (44.81773, -122.56006) .509°, 752.5 mb, 1831.0 m

Cirrus and cirrostratus aloft now, sun breaking through.

Moderate (20-24 dBz) echoes to E 30-40km in fore scan.

233024 Z (45.02323, -122.37131) 88.784°, 694.5 mb, 1963.0 m

Hit pt. B, now heading E and up to 11,000 ft.  Quickly back into solid pcp; needles and columns; occ supercooled droplets; T=-5.0 C

234639 Z (44.07178, -122.08182) 178.854°, 670.3 mb, 1720.0 m

Leg C-H; heavier pcp definitely to the W, not to the E; near and slightly above cloud top most of this leg (11000 ft)

000554 Z (44.49175, -121.61642) .336°, 618.2 mb, 2692.0 m

Fairly boring I-D leg; overcast above, undercast too;

dual doppler showing shallow, spotty echoes to the E of the crest.

More consistent echoes to W between 20-60km

Visually, cloud top is deeper to the W.

Very dry air up here...11% RH and Td as low as -30 C!!!

001611 Z (44.95650, -121.49205) 183.439°, 618.1 mb, 3143.0 m

41 miles to K, hit burst of pcp just SE of pt. D

Td up to -9

Rimed looking ice in cld phys

001912 Z (44.74217, -121.51292) 184.033°, 618.1 mb, 2936.0 m

Shallow cloud below, in fact, breaks in clouds visible 24 miles to K

Nice view!  Snow on ground...skiing anyone?

002434 Z (44.36786, -121.45424) 124.980°, 619.5 mb, 3061.0 m

Beginning descent to 500 feet AGL at Sisters Airport...

11000:  cloud top

9000:  rimed columns ... T/Td: -3/-4

7500:  freezing lvl; cloud base nearly coincident

 

003055 Z (44.09501, -121.12379) 318.655°, 736.8 mb, 1589.0 m

Climbing back up from about 6000 feet...

8000: hit cloud base again

10000: occasional needles/columns; T/Td: -3.5/-3.5

11500: cloud top

13500: very dry air aloft; T/Td: -9.0/-25.0

14500: T/Td: -11.0/-37.0

 

004037 Z (44.21339, -121.74120) 232.934°, 615.2 mb, 2372.0 m

Headed SW to G, 13000 feet

Suddenly hit saturation; T/Td: -9.7/-10.0

Dual doppler showing moderate echoes 5-20 km to NW

 

004557 Z (44.01340, -122.10869) 232.812°, 695.4 mb, 1604.0 m

25 miles to G...overcast thickening, slight turbulence

Descended to 10000 feet

Supercooled water here;  T/Td:  -3.0/-3.0

8000 feet:  freezing level...drizzle drops

005214 Z (43.79205, -122.52101) 232.995°, 750.2 mb, 1829.0 m

At G, turning to head N

Alt:  8070; T/Td: 0.6/0.6

Dual doppler paints embedded convection with pretty high echo tops 20-40km to theW.

005605 Z (44.00900, -122.57747) 1.434°, 750.5 mb, 1762.0 m

Echoes creeping closer as we move N, fore scan shows a 24-28 dBz cell about 25 km to the W.

56 miles to B

010253 Z (44.47274, -122.56552) 359.646°, 750.6 mb, 1631.0 m

Dual doppler showing significant echo in this region and extending to the E about 30 km.  Echoes around 28 dBz.

Flight level is just below the melting level (8070 feet).

010659 Z (44.75183, -122.56433) 359.728°, 750.5 mb, 2141.0 m

Nearing B (15 miles to it)...

Temperature slightly lower, now below fzg;  T/Td: -0.3/-0.3

Dual doppler showing moderate convection 20 km to the E in both aft and fore scans.

 

011416 Z (45.02063, -122.18108) 90.436°, 670.2 mb, 2093.0 m

Nearing C (3 miles)...

supercooled water at 11000 feet; T/Td: -5.0/-5.4

some turbulence as we head south of C

mixture of crystals and supercooled droplets

011646 Z (44.90257, -122.07399) 182.668°, 668.1 mb, 1886.0 m

Heavier pcp showing up 5-10 km to the W.

Drying out a little bit at flight level;  T/Td: -6.0/-11.6

 

012412 Z (44.40771, -122.08272) 179.910°, 668.1 mb, 2108.0 m

Heavier pcp now over 10km to W.

Main pcp appears to be 15-30 km to W.

Not really in cloud at this time, but picking up crystals nonetheless.

Crystals probably being carried by slightly stronger W wind aloft after being carried out of the top of the embedded convection to the W.

 

Hit pt. H; now heading NW to a point W of S-POL to begin W-E stack

014129 Z (44.02298, -122.52454) 292.409°, 554.0 mb, 3927.0 m

z=16000 feet

Still dry up here;  T/Td: -14.5/-35.7; RH: 14%

 

021654 Z (44.38802, -122.59798) 272.390°, 569.4 mb, 4244.0 m

Finished E leg at z=16000 feet; now headed W at z=15000 feet (about 4.5 km)

clear air

022628 Z (44.40033, -123.43687) 272.012°, 595.2 mb, 3993.0 m

z=14000; nearing W point of W-E stack

clear air

023804 Z (44.41163, -122.35083) 88.715°, 595.9 mb, 3329.0 m

finally starting to see some meaningful echoes again

most of the action appears to be to the N

22 miles to Santiam Pass

grazing cloud top from time to time

not a smooth of a ride anymore

024912 Z (44.37727, -121.61859) 293.549°, 644.9 mb, 2532.0 m

 

Hit eastern point (O), pcp is dying out...

heading W again and descending to 10000 feet

last leg

025153 Z (44.38393, -121.83156) 271.601°, 672.6 mb, 1906.0 m

Seeing a mixture of supercooled droplets and columns on this leg

T/Td: -5.0/-5.5

z=10300

025512 Z (44.38754, -122.07114) 268.706°, 701.9 mb, 1299.0 m

weak echo here...seeing some ice crystals now

T/Td: -3.0/-3.0

z=9500 feet

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

021123 Z (43.78807, -122.52592) 123.970°, 710.9 mb, 2223.0 m

Lots of needles.  At G.  T/Td=-3/-5.2 148/60

Majority of BG flown at about 8450ft except initial part when still climbing. B->G time:22mins 10 secs.

021409 Z (43.78519, -122.21391) 86.534°, 659.0 mb, 2452.0 m

Reached H after Climb to 11400ft.  T=-8.4/-7.7  Very few cloud particles.  246/75.  G->H 4 mins 20sec.

021823 Z (44.03703, -122.07861) 358.048°, 658.9 mb, 1934.0 m

58 miles from C.  Radar  is really thinning except to NW.  T/Td=-9.3/-8.5; 238/60.  Much more turbulent than first lawn mover leg.

022749 Z (44.73656, -122.08429) 1.152°, 658.2 mb, 2190.0 m

Just hit an updraft (poss gravity wave) at about 2:26:20.  Jump in cloud particles and precip. At about the same time.  Radar has really filled in again.  Fair amount of large crystals.

023112 Z (44.99904, -122.07504) 23.138°, 643.6 mb, 2836.0 m

At point C.  H->C 16 mins.  Climbing to 13K at heading to D.

023247 Z (45.05436, -121.91560) 80.380°, 604.2 mb, 2899.0 m

Levelled at 13600 and making the turn 10 miles from D.  T=-13.  Dewpoint sensor just failed ( possibly iced up).  Slowly coming back to life. C->D 4mins 28sec

023533 Z (45.02706, -121.60718) 171.953°, 608.1 mb, 2819.0 m

Heading towards I.  T/Td=-11.6 (Dewpoint still all over the place).  245/60.  Fairly ice crystals.  Td settling down to about -11.5C.  Good radar to west.  Looks like some embedded convection,  Thinner to the east.  Hitting some more bumps.  3M/s at approx 2:40:30.

025855 Z (43.85142, -121.65674) 9.896°, 607.9 mb, 2467.0 m

Just passed I.  Data at I:  T/Td -12.4/-12.8 248/72.5.

D->I 22mins 50secs.  Leg done at 13473.  Not doing JE leg.  Now heading to K for slow descent to F.  Nice dendrites.

030332 Z (44.24029, -121.54128) 11.165°, 607.9 mb, 2920.0 m

Can see upslope in radar and shallowing echo in the lee around the 20 km range ring.

030450 Z (44.31419, -121.57469) 251.429°, 608.2 mb, 2965.0 m

At K, 13460ft.  Leg time: 7min 22sec.  T=-11.5; td=-15.9; 251/63

030914 Z (44.20963, -121.88518) 243.084°, 613.3 mb, 2404.0 m

13200: T/Td=-12/-12.2.  250/62

12925: T/Td=-11.3/-11.7 252/67

12000: T/Td=-10/-10.1 248/62

T=-8: z=11150ft; Td=-8.8; 250/63

11000: T/Td=-7.6/-8 250/60  Transition to mostly needles

10000: T/Td=-6.9;-6.3 250/52  Moderate turbulance 10100-10000.

9000: T/Td=-5.3/-4.6 253/51 Still mod turb.

T=-4: z=8230ft; Td=-3.3 245/53.

8000: T/Td=-3.6/-2.7; 247/49

Rimed crystals and aggregates.  Moderate turb.

6500:  T/Td=-0.8;-0.9; 257/36.

Moderately severe turb.  Good radar coverage.  Cloud depth still about 6km.

032619 Z (43.80268, -123.03801) 330.302°, 797.1 mb, 1651.0 m

At point F.  T/Td=-1.2/-0.8; 258/44

K->F 21min 45sec

033008 Z (44.06456, -123.03282) .425°, 797.2 mb, 1699.0 m

Nice view down below of Eugene!  Much less precip. Here. Pretty smooth.

033239 Z (44.23717, -123.03268) 358.915°, 797.5 mb, 1716.0 m

Slight chop.

033747 Z (44.58102, -123.03406) 359.874°, 797.2 mb, 1735.0 m

Significant turb at 3:36:30.  8m/s vertical motion.

033946 Z (44.71900, -123.03276) 359.356°, 797.5 mb, 1750.0 m

Very little radar coverage at the moment.  Almost no precip.  A little cooler towards A too. T/Td=-2.2/-2.4 256/47.  Can see Salem

034239 Z (44.91833, -123.03246) 357.954°, 797.4 mb, 1752.0 m

Nose radar indicates a few cells ahead.  And it was right!

 

034422 Z (45.03324, -123.00653) 52.561°, 796.0 mb, 1760.0 m

Made the turn at A.  Hit a big bump.  +7.5 and -10.0. Approx 3:44.

Climbed to 9500 heading to C.

Moderate to moderately severe chop. T=-6.6/-6.3 249/58

F->A 18min 50sec.

034955 Z (45.05311, -122.38309) 91.384°, 708.6 mb, 1851.0 m

12 miles from C 9570ft.  Radar coverage increasing again as we near the crest.  Now climbing  to 11000ft

035157 Z (45.05337, -122.14508) 92.811°, 658.5 mb, 2444.0 m

2.5 miles from C.  11465Ft.  Making the turn.  T/Td=-9.9/-10.6  258/55.  Needles and plates.  Heading to H.

A-> C 8 mins 25 sec

040230 Z (44.40169, -122.08786) 178.701°, 657.9 mb, 2129.0 m

37 miles from H.  T/Td=-10.6/-12 251/55

Moderate chop.  Good dual dopplar coverage

041230 Z (43.75751, -122.01875) 82.840°, 644.4 mb, 1866.0 m

At point H.  T/Td=-10.5/-10.9 256/47

C->H 19 min 50sec

Leg flown at 11468ft.  Fairly smooth until 6 miles from H, then slight chop.

041315 Z (43.79543, -121.95770) 25.337°, 624.4 mb, 2051.0 m

Climbing to 13K

-14C@13450ft  Td=-16F.  Heading to Q at 13500ft.  Good radar coverage in this area    Some cells off to the r

042236 Z (44.50196, -121.54060) 23.526°, 607.4 mb, 2810.0 m

2 miles from Q at 13500.  About 5 mins ago saw amazing St.Elmos fire on the Cockpit window.  Just like a plasma ball.  I wonder what the ice crystals looked like.

T/Td=-14.2/-16 252/63.

042542 Z (44.56725, -121.62730) 239.508°, 618.9 mb, 2943.0 m

Descent to 10500:

12000:T/Td= -11.2/-12.2 263/55.  Slight chop.

11000:  T/Td=-9/-10.8 261/51

Moderate chop at 10500ft.

043048 Z (44.42516, -121.95438) 240.069°, 684.9 mb, 1820.0 m

Moderate to moderately severe turbulance.

 

043339 Z (44.34417, -122.14482) 237.510°, 683.0 mb, 1718.0 m

Fairly high frequency turbulence.  Radar sketchy to right (NW), but good coverage to left (SE) with some embedded convection.

043710 Z (44.24981, -122.36620) 240.271°, 684.1 mb, 2100.0 m

36 miles from P.  Much calmer air.  T/Td=-9.7/-14  246/56.  Almost no precip at flight level

043912 Z (44.19259, -122.49872) 239.014°, 683.5 mb, 2423.0 m

More moderate chop.  28 miles from P.  Main echo still off to left, much less to the right, though it seems to be weakening everywhere now especially foreward scan.

044740 Z (43.94512, -123.06372) 221.651°, 683.9 mb, 2881.0 m

At P t/td=-10.5/-12 250/38.  QP leg 24min 25sec.

Climbing to 11500 feet heading to pt H.

045132 Z (43.85425, -122.72160) 98.068°, 660.9 mb, 2591.0 m

Experiencing some moderate chop. 4:48:37 VV=7m/s.

22 miles from H.  Z=11400ft.  T/Td= -12.1/-12.8 246/58

045647 Z (43.79759, -122.12804) 73.223°, 660.3 mb, 2164.0 m

2.5miles from H.  T/Td=-11.4/-14.2 253/65

PH leg: 9mins 25 secs.  Starting H->C at 11400ft

050117 Z (44.11195, -122.08255) 359.948°, 660.1 mb, 1752.0 m

Moderate turbulance.  Radar really filling out again to east with terrain enhancement.  Can see eacho sloping up the terrain.

050656 Z (44.52946, -122.08780) 359.636°, 659.5 mb, 2335.0 m

Short burst of dentrites and/or hex columns interupting the previously boring crystals.  T=-12.2; Td=-12.8

051019 Z (44.78056, -122.08989) .205°, 660.2 mb, 2236.0 m

Haven't seen a detectable wind shift but its getting colder along this leg.  At H it was -11.4/-14.2.  Now it is -13/-13.  Humidity is fluctuating rapidly between supersaturated and about 90%.

051328 Z (45.00151, -122.08720) 359.738°, 660.1 mb, 2475.0 m

At C:  z=11400ft  A->C 16mins 35secs

T/Td=-12.5/-13F.  246/47.

Now climbing out to cruising altitude and heading home.

051656 Z (45.22256, -122.20308) 334.582°, 576.4 mb, 3772.0 m

14000: T/Td=-19.1/-19.1

15500: T/Td=-21/-27.6

16500: T/Td=-24/-25.5 242/49

Level at 16600: T/Td=-23/-27 246/47

Above precip. But a fair depth of ice still overead.

055332 Z (47.74178, -122.55676) .859°, 853.7 mb, 1118.0 m

Heading into final approach.  4700 feet.  Starting to hit some chop.  Wind 270/10kts, not seeing the expected strong southerlies yet.

4000ft:270/28. 1.6C VV:+- 5m/s

3500ft300/95.3

3000ft:3.2/2 297/11

2500ft:4/3.4 297/2

2000ft:5.3/3.2 199/8

 

060951 Z (47.90208, -122.28159) 104.958°, 964.8 mb, 10.0 m

Landed about 0607Z.  Taxi to hangar.

061130 Z (47.90023, -122.28058) 261.763°, 964.9 mb, 10.0 m

Engines off.