TIMES WHEN A/C WAS IN OR VERY NEAR ANVIL and PASS NUMBER

Jim Dye and Sharon Lewis
Analysis last updated Sept 2, 2003


ANVIL DEFINITION

To be considered "In-Anvil" a cloud must:

1) be morphologically an anvil, ie. it has been produced by a downshear or upshear outflow or blow-off from a cumulus convective core. The convective core may either still exist or have decayed, ie. the anvil can be attached or detached. This requires determining the previous history of the cloud in question. Debris left in place at higher altitudes from once active convective cores growing in a low shear environment is NOT considered to be an anvil.

2) have a radar base at or above 5 km -- i.e., be an all-ice cloud with no possible melting going on.

3) be "penetrated" by the A/C -- generalized to include flight levels not more than 2 km above radar top or below radar base at the position of the aircraft. The reason for this extension is to include any cases when the aircraft is near an anvil that might have high fields that are not screened.

Times of anvil passes were determined using the first entry into and last exit from either radar and/or particles, but if particles persisted for >1 min after no return, the anvil type is designated 8. When continguous radar returns existed within 2 km vertically above or below the A/C those times were included as part of the pass.

Anvil Types
10 -- A/C in distinct anvil with base >= 5 km altitude
9 -- anvil without apparent core
8 -- A/C in particles but no radar return. (only used for periods >1 min)
6 -- anvil but with gnd clutter and other low level returns
4 -- Anvil with distinquishable base, but base below 5 km. If base not continuous, used >50% of pixels below 5 km as criteria. Do not include case if radar range is too far to determine base.
3 -- A/C way below the anvil during takeoff, landing or cabin press. loss
0 -- This designates NON-ANVIL, the aircraft was flying in something other than an anvil.

Date Begin      End                   Anvil Pass Comments
TypeNos
000604
210030 210220 10 1.1 A/C is S-L flying toward core
210410 210510 10 2.1S spiral
210630 210810 10 2.1S same spiral
210950 211200 10 2.1S same spiral
211320 211600 10 2.1S same spiral
211640 212210 10 3.1 big spiral
212410 212700 10 4.1 S-L & turn
212700 213210 10 5.1 S-L & turns
213820 214330 10 6.1 " "
214510 214640 10 7.1 S-L
215410 215720 4 8.1
215720 220050 10 9.1
221220 221430 10 10.1
221430 221530 4 10.1
221530 221630 10 10.1
224300 224500 10 11.1
225150 225340 10 12.1
225750 230050 10 13.1
000607 Cabin Press leak terminated flight early;
181710 181840 6 1.1 only small fragment of anvil, cluttered
183050 183400 6 2.1 " " " "
183630 183820 6 3.1 " " " "
000611
181610 181900 6 1.1 mid-level anvil
181900 182120 10 2.1
182840 183320 10 3.2S mostly spiral at one altitude
183320 183930 10 4.2 S-L & turns below anvil
183930 184900 10 5.2
184900 185320 10 6.2
185320 185540 8 6.2 in particles, but no radar echo
185540 185840 10 6.2 just below weak return
190000 190120 8 7.3 in particles, no return
190120 190350 10 7.3
190350 190450 4 7.3
190850 191250 10 8.3
191540 191820 10 9.3
192900 193200 10 10.3
193200 193530 10 11.3
193930 194320 10 12.3
194740 194950 10 13.4 mostly under weak anvil on way home
000613
204550 204900 10 1.1 across anvil passes until 2225
205100 205300 10 1.1
205510 205740 10 2.1
205920 210230 10 2.1
210310 210820 10 3.1
211250 211500 10 4.1
211720 212130 10 4.1
212130 212700 10 5.1
213040 213630 10 6.1
213630 214040 10 7.1
214330 214510 10 7.1
214910 215420 10 8.1
215200 215420 0 9.1
215420 215530 4 9.1
215730 215850 10 9.1
220130 220300 4 10.1
220300 220730 10 10.1
220850 221330 10 11.1
221330 221500 4 11.1
221900 222030 4 11.1
222400 222540 4 12.1
222540 223120 10 12.1 1st pass to NE; parts extend beyond radar
223120 223400 8 12.1 particles but no radar return
223939 224220 8 13.1 Particles but no radar; flying SW
224220 225010 10 13.1
225010 225220 4 13.1
225310 225730 4 14.1
225730 230350 10 14.1
230350 230500 8 14.1 particles but no radar return
231210 231530 8 15.1 parts no radar
231530 232010 10 15.1
232010 232410 4 15.1 anvil base below 5 km
232620 233100 4 16.1
233100 233320 10 16.1
233320 233520 8 16.1
234610 234820 10 17.1
234820 235420 4 17.1
235540 235940 4 18.1 low base
235940 240420 10 18.1
000614
21270021334091.1
21334021373041.1debris below A/C; should we include
21390021471092.1
21502021572093.1
221450221650104.2near edge of anvil
221930222430105.2pass extends into core
223030223630106.2" " "
224040224630107.2old anvil merged with new
22463022513047.2in sediment. zone near core
225250225700108.2turn 180 in anvil
225700225930109.2
2259402303101010.3anvil from newer cell
2315002318301011.3across new anvil
2321202325301012.3across anvil
2329102333301013.3across anvil
2335002340301014.3across
2347102357001015.3along axis toward core
2357002407301016.3along axis away core
000628_2
182320 182650 9 1.1s spiral in anvil 1
182800 183100 9 1.1s spiral in anvil 1
183200 183420 9 1.1s spiral in anvil 1
183430 183630 9 1.1s spiral in anvil 1
184510 184710 6 2.1
184940 185220 10 3.2 a/c turns around in anvil 2
185540 185640 10 4.3
185730 185930 9 5.1
190040 190200 6 6.3
190420 190710 6 7.2 a/c turns around in anvil 2
191010 191100 6 8.3
191130 191230 6 9.1
191330 191440 6 10.3
191640 191900 10 11.2
191900 192120 10 12.2
192150 192410 10 13.2
192440 192740 10 14.2
193050 193700 10 15.2
193700 194320 10 16.2
194620 195900 10 17.
200310 200430 10 18.4
201320 201720 10 19.4
201730 201950 10 20.4
202000 202130 10 21.4
202800 203030 4 22.4
203100 203300 10 23.4
204300 204610 10 24.4
204620 204820 10 25.4
204950 205240 10 26.4
205340 210150 10 27.4
210250 210830 10 28.4
210850 211500 10 29.4
010525 A/C flew mostly 6,7 & 5 km altitude this day
190150 190240 4 1.1
190240 190600 10 1.1
190600 190910 10 2.1 S&L and turns
190910 191040 4 2.1s
191040 191400 10 3.1 turns and S-L
191400 191820 10 4.1
191910 192030 4 4.1
194520 194650 4 5.1 locale where 21x21 has violators
194650 195000 10 5.1
195000 195430 10 6.1
195430 195830 10 7.1
195830 200300 10 8.1
200300 201000 10 9.1
201000 201500 10 10.1
201500 202340 10 11.1
202340 202750 10 12.1
203440 204210 10 13.2
204450 204730 6 14.2 mostly turns
205900 210130 10 15.2
210130 210430 10 16.2
210500 210600 10 17.2
210640 210740 10 18.2
210740 211020 4 18.2
211330 211520 10 19.2
211520 211720 4 19.2
After ~2144 A/C in the radar cone of silence to end of flight.
010527
215940 220510 10 1.1 next passes many small legs & turns
220510 220630 8 2.1
220640 220940 10 3.1
221030 221220 8 4.1
221220 221610 8 5.1 sporadic radar return
221710 221900 10 6.1 " " "
222120 222530 8 121 only small particles
222530 223000 10 13.1
224230 224700 10 11.1
224700 225430 10 21.1
224700 225430 10 12.1
225430 230000 10 13.1
230000 231100 10 14.1
231100 231530 10 15.1
231750 232140 10 16.2
233410 233620 10 17.2
234840 235000 10 18.2
240840 241030 4 19.2
241030 241630 10 20.2
241630 242110 10 21.2
After 2110 the track is no longer reliable. Problems with FSSP this day -- not reliable.
010528
194630 194850 10 1.1
195120 195340 10 2.1
195410 195900 10 3.1
200140 200350 10 4.2 thin, weak anvil layer
200350 200500 8 5.2 " " " "
200500 200610 10 5.2
200610 201030 8 5.2
202000 202140 10 6.1 back in first cloud system
202350 202530 6 7.1
202910 203010 4 7.1
203210 203330 10 8.1
204100 204340 10 9.1
204340 204640 10 10.1
010529
202630 202810 10 1.1 case with small anvil
205610 205730 10 2.1
205950 210110 10 3.1
211520 211820 10 4.1
212140 212640 10 5.1
213730 214250 10 6.1
214620 215040 10 7.1
215040 215310 4 7.1 becoming mid-level stratiform s
220130 220850 10 8.1 system rather than anvil
221100 221740 10 9.1
221740 221930 4 9.1
010602
192800 192920 10 1.1
193110 193410 10 2.1
193910 194330 10 3.1 74C atten in later part of pass
194330 194950 10 4.1 74C atten. in early part of pass
195720 195940 8 5.1 brushed edge of anvil
200010 200240 10 5.1
201330 201540 4 6.1
201540 201700 10 6.1
201700 202010 8 6.1
202010 202200 10 7.1
202200 202310 4 7.1
203420 203620 10 8.1
203620 203850 10 9.1
211340 211600 10 10.1
211600 211930 10 11.1
211930 212050 4 11.1
212050 212920 10 12.1S
215110 215420 10 13.1
215420 215620 8 13.1
215620 220130 10 14.1
222130 222630 10 15.1
222630 223200 10 16.1
223200 223650 10 17.1
224220 224800 3 18.1 A/C way below the anvil - landing
after ~2030 on this day scan gaps are bad because of A/C range from radar
010604
190340 190610 10 1.1
190820 190950 10 2.1
191730 192100 8 3.1
192100 192500 10 3.1
192500 192810 10 4.1
193440 193940 10 5.2
194100 194530 10 6.2
194940 195410 10 7.2
195700 200140 10 8.2
200210 200400 10 8.2
200530 200850 10 9.2
200900 201150 10 10.3
201500 201900 10 11.3
201900 202630 10 12.3
202630 203610 10 13.3
203610 204800 10 14.3
204800 204950 8 14.3
204950 205820 10 15.3
205820 205940 8 15.3
210010 210430 8 16.3
210430 210900 10 16.3
210900 211240 10 17.3
211240 211740 4 17.3
211740 212100 10 18.3
212100 212530 4 18.3
212530 212930 10 19.3
212930 213200 10 20.3
213200 213650 4 20.3 74C scan gap, NEXRAD shows anvil below 5 km
213650 213830 10 21.3
213830 214110 10 22.3
214110 214900 4 22.3
214900 215300 10 22.3
215300 215700 10 23.3
215700 220310 4 23.3 74C or NEXRAD shows base below 5
220310 220550 10 23.3
220550 220720 4 23.3 " " " "
220720 221510 4 24.3 " " " "
221510 222000 10 24.3
222000 222520 10 25.3
222530 222930 4 25.3 " " " "
222930 223520 4 26.3S NEXRAD intermittent shows base below 5 km
223520 224300 10 26.3S
224300 224940 4 27.3 74C or NEXRAD shows base <5 km
224940 225839 3 28.3 A/C descending toward base below anvil
010610
202230 202520 3 1.1
202520 202630 10 1.1
204150 204530 4 2.2
204530 205830 4 3.2
210140 2106 4 4.2
2113 211450 10 5.2
211450 211730 4 6.2
211730 211950 10 6.2
211950 212210 4 6.2
212210 2125 10 6.2
2125 212840 10 7.2
212840 2130 4 8.2
2130 2131 10 9.3
2131 2134 10 10.3
2134 2136 4 10.3
2136 2138 10 11.3
2138 214140 4 11.3
214140 214320 10 12.3
214320 2147 4 13.3
215020 215320 4 14.3
215320 2155 10 15.3
2155 220030 10 16.3
2211 221330 4 16.4
221330 221730 10 17.4
222950 2233 10 18.4
2233 223530 10 19.4
223530 224040 4 20.4
2246 224840 10 20.4
224840 225020 4 21.4
225930 230120 10 22.5
010615
2136 213840 4 1.1
2146 2148 10 2.1
2148 215550 10 3.1
2157 2206 10 4.1
2206 221550 10 5.1
2217 2225 10 6.1
2225 2233 10 7.1
2233 2240 10 8.1
2240 224430 10 9.1s
224430 2250 10 10.1
2250 2252 10 11.2
2300 230140 10 12.2
010624
1808 1810 3 1.1
1810 181530 10 1.1
181530 1819 10 2.1
182220 182710 10 3.1
183010 1835 10 4.1
183530 1841 10 5.1
184220 184940 10 6.1
1851 185810 10 7.1
185930 1904 10 8.1
1904 190950 10 9.1
191320 1920 10 10.1
1920 192730 10 11.1
193040 1939 10 12.1
1939 1947 10 13.1
1947 195450 10 14.1s
195510 1957 10 14.1s
195750 195930 4 14.1s
200110 200220 10 14.1s
010625
195240 195330 3 1.1
195330 195940 10 1.1
195940 2010 4 1.1
2010 201410 4 2.1
201410 201640 10 2.1
201640 2018 4 2.1
2018 2022 10 2.1
2022 203320 10 3.1
203730 2045 10 4.1
2045 204810 10 5.1
204830 2057 3 6.1
2123 2130 3 0
213120 2137 3 0
213840 221430 3 0
010627
145710 1503 3 1.1 a good anvil, but > 2km below base
1503 150620 10 2.2
151950 1524 10 3.1
153120 153250 10 4.2
153410 1535 10 5.2
1535 1537 10 6.2
153920 154040 4 7.2
154820 1554 10 8.2
1557 1601 10 9.2
161020 161130 10 10.2
161640 1623 10 11.3
1623 1625 5 12.3
163450 164040 6 13.4
164400 164720 10 14.4 less than 50% below 5 km
165040 165420 10 15.4
165420 165720 4 16.4
1657 1700 6 17.4
1700 170220 10 17.4
170410 170520 10 18.4
171140 171530 10 19.5