Global Hawk #872 09/26/12 - 09/27/12

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Flight Number: 
872-0101
Payload Configuration: 
HS3 - TN872 2012 config
Nav Data Collected: 
No
Total Flight Time: 
25.4 hours
Flight Segments: 
From:WFFTo:WFF
Start:09/26/12 10:31 Z Finish:09/27/12 11:53 Z
Flight Time:25.4 hours
Log Number:12H002PI:Marilyn Vasques
Funding Source:Hal Maring - NASA - SMD - ESD Radiation Science Program
Purpose of Flight:Science
Comments:The sixth science flight for HS3 2012 was the fifth flight to Nadine. 75 sondes were deployed and all instruments collected data. The flight path was altered near the end of the encounter with Nadine to accommodate 3 square patterns around the center of circulation.
Flight Hour Summary: 
12H00213H008
Flight Hours Approved in SOFRS327
Flight Hours Previously Approved 178.1
Total Used148.946
Total Remaining 132.1
13H008 Flight Reports
Date Flt # Purpose of Flight Duration Running Total Hours Remaining
10/06/12872-0102Science7.37.3170.8
10/12/12872-0103Ferry9.717161.1
11/01/12871-0082Check4.821.8156.3
11/05/12 - 11/06/12871-0083Science24.246132.1
12H002 Flight Reports
Date Flt # Purpose of Flight Duration Running Total Hours Remaining
08/28/12872-0094Check5.55.5321.5
08/30/12872-0095Maintenance0.76.2320.8
09/06/12 - 09/07/12872-0096Science19.325.5301.5
09/11/12 - 09/12/12872-0097Science25.751.2275.8
09/14/12 - 09/15/12872-0098Science22.473.6253.4
09/19/12 - 09/20/12872-0099Science24.898.4228.6
09/22/12 - 09/23/12872-0100Science25.1123.5203.5
09/26/12 - 09/27/12872-0101Science25.4148.9178.1

Flight Reports began being entered into this system as of 2012 flights. If there were flights flown under an earlier log number the flight reports are not available online.

Related Science Report: 

HS3 - Global Hawk #872 09/26/12 - 09/27/12 Science Report

Mission: 
HS3
Mission Summary: 

Hurricane and Severe Storm Sentinel (HS3) Mission

 

HS3 2012-09-26 Flight Report: GLOBALHAWK AV-6

 

Flight Scientists:

Shift 1 (0800-1700 UT): Scott Braun, Pete Black

Shift 2 (1700-0100 UT): Paul A. Newman, Jon Zawislak

Shift 3 (0100-0900 UT): Mike Montgomery, Jason Sippel

Shift 4 (0900-1300 UT): Scott Braun, Pete Black

 

Lessons Learned:

Email lists need to be tested – we keep getting kickbacks on the HS3-Mission-Science

WE NEED HDVIS

WE NEED THE LOW-LIGHT CAMERA IN MTS

Given the opportunity to circumnavigate the center several times, depending on the latency of sonde data in MTS, one should check to see where data has dropped out for choosing future drop locations

 

26 September 2012

 

Take-off: 1030Z

 

Nadine VIS for 0930Z and 1015Z showing developing convection and upper swirl NE of low-level center and numerous small rainbands W and N of center in ‘cool sector’ distinct from towering cu SE and E of center in ‘warm sector’.

 

Nadine IR (upper) and SSMIS 85 GHz at 10Z showing enhanced convective development N and NE of center with hook indicating upper level center displaced  N of low level center.

 

VIS at 11Z shows three distinctive cloud types in environment around Nadine: Benard open and closed cells in maritime arctic air mass N and NE of Nadine, closed Benard cells NW thru SW of Nadine representing martime cool, dry airmass and towering CU S thru E of center indicating warm, moist tropical air mass.

 

TRMM 85- (upper) and 37-GHz (lower) for 0835Z showing beginning of convective development NE of low-level center.

 

Nadine 3-hr structure change in IR (top) and VIS (bottom) showing enhanced convective activity wrapping around the eye forming the initial stages of a large, closed eyewall. Cirrus shield is expanding- IR cloud top temperatures are warming, while expanding in area.

 

MODIS VIS and Water Vapor images at 1241Z of Nadine eyewall and mesovortex.

 

MODIS aqua water vapor at 1554Z (below):

 

Drop 1: 1211Z – good data all the way to the surface

Drop 2: 1638Z – slight delay after turn; 1st drop in pattern on northern most east-west leg

Drop 3: 1648Z

Drop 4: 1658Z

Drop 5: 1708Z

Drop 6: 1718Z

Drop 7: 1728Z – data looking good on all sondes so far

Drop 8: 1738Z

Drop 9: 1747Z

1756Z: Discussion with forecasters to move the third east-west leg north by 20-24 nmi to cross the center. MODIS pass at 1241Z (see above) estimate center of mesovortex at approximately 30.9N/29.9W; 1500Z NHC advisory indicates center of 30.6N/30.3W; 1730Z MSG-2 visible (below) indicates approximately 30.5N/30.4W. Slow movement W/SW. There may be a misalignment of what we’re seeing in the middle cloud and the lower level mesovortex.

Drop 10: 1758Z

Drop 11: 1809Z – after turn at G02

1815Z: High cloud tops have rotated around from the northern quadrant to west/southwestern quadrants

Drop 12: 1822Z – middle drop between G02 and G03

1826Z: Discussed to NOT drop 18 and 20 and save those for the 3rd west-east leg across the center, when we can do 3.5 minute drops in the eye

Drop 13: 1835Z – after turn at G03

Drop 14: 1844Z

1815Z visible image from MSG-2 (below) – corresponds to the CPL capture 1847Z in northeast quadrant cirrus outflow on east-west leg G03-G04 (see visible and CPL image below):

1850Z: Request pilots to move third leg (west-east across center; G05-G06) 24 nmi to north – new latitude is 30 deg. 24 min.

Drop 15: 1855Z

1900Z: Have told the pilots that we will move east-west leg G07-G08 up 60 nmi (~1 deg. Latitude) north and west-east leg G09-G10 up 90 nmi (~1.5 deg. Latitude) north. This will allow CPL to overfly some cloud bands on the southern side.

Drop 16: 1905Z – reporting some interference in the low-level winds but overall thermodynamic and wind information has been good so far.

Drop 17: 1915Z – skipping D18 – now will be 10 minutes between drops

Drop 18 (former D19): 1927Z

Drop 19 (former D21): 1935Z

1940Z: Will soon be re-filing ALL changes to legs at request of the pilots (rather than 2 separate changes – 1) the northward change to 2 southern most east-west legs and 2) the north-south leg at the end of the pattern). G07-G08 moved 1 deg. North to 28.5N latitude; G09-G10 moved 1.5 deg. North to 26.5N latitude; still working on final north-south leg across center => forecasters indicate will remain unchanged.

CPL screen capture from 1945Z corresponding to IR capture below:

Drop 20 (former D22): 1946Z

Drop 21 (former D23): 1956Z

1957Z: Email drop change on 3rd east-west leg across center. Instead of 5 min intervals, will be drop a sonde at 3 min 20 sec. intervals - between D30 and D34 (salvo).

Drop 22 (former D24): 2012Z after the turn G04

Drop 23 (former D25): 2022Z

Drop 24 (former D26): 2034Z after the turn at G05

Drop 25 (former D27): 2042Z

SSM-IS overpass of Nadine at 1949Z. Center appears to be near 30N/31.6W (below):

Drop 26 (former D28): 2051Z

2056Z: Higher cloud tops have rotated around to the southern side of the eye as we make the west to east pass over the center.

Drop 27 (former D29): 2101Z west of center into some higher cloud

Drop 28 (former D30): 2111Z – begin 3 min 7 sec. interval drops over center

Salvo:

Drop 29 (former D31): 2114Z

2115Z: May be seeing clearer center in HDVIS south of flight path

Drop 30 (now D31.1): 2117Z – near center

Drop 31 (former D31): 2120Z – near center

Drop 32 (Drop 32.2): 2123Z – east of center

2045Z IR pass of Nadine is shown below (shortly ~25-30 min prior to pass over the center). We just missed the clearer center in the satellite to the north (went directly over northern reach of inner cloud band) – drops should still give us good information on whether the low-level center is displaced.

CPL screen capture from 2125Z after pass of center (below).

Another look with IR at 2115Z around the time of center pass (below):

Drop 33 (former Drop 33): 2127Z – east of center

Drop 34: 2130Z. Previous drops appear to be getting to low levels

End of Salvo

Image below shows the 2115Z IR image and 2139Z aircraft location. Corresponding CPL image is below screen capture.

2145Z: Request pilots to skip D43 (southeast quadrant) and add a drop between D46 and D47 (southwest quadrant) – so 5 minute separation between 46, 46.1 and 47. Accepted.

2154Z: Looking at dropsondes on the 2nd east to west leg – 30 kt northeasterlies found at low levels

Drop 35: 2140Z

Drop 36: 2149Z

Drop 37: 2201Z – after turn at G06

Drop 38: 2209Z

Drop 39: 2219Z – after turn at G07

Drop 40: 2229Z - now on east to west leg between G07-G08

Drop 41: 2238Z

Drop 42: 2248Z

Drop 43 (former D44): 2258 – entering cloud shield


From NHC discussion at 0500PM EDT update:
NADINE CONTINUES TO PRODUCE ORGANIZED CONVECTIVE BANDING...NOW

PRIMARILY OVER THE SOUTHWESTERN SEMICIRCLE.  AN EARLIER OSCAT

OVERPASS SHOWED 40 KT WINDS IN THE NORTHWESTERN QUADRANT...AND THE

SATELLITE INTENSITY ESTIMATED FROM TAFB HAS INCREASED TO 45 KT.

BASED ON THESE...THE INITIAL INTENSITY REMAINS 45 KT.  NADINE IS

PRODUCING GOOD CIRRUS OUTFLOW IN ALL DIRECTIONS EXCEPT FOR THE

SOUTHEAST.  HOWEVER...DROPSONDES FROM THE NASA GLOBAL HAWK AIRCRAFT

NORTH OF NADINE SHOW 35-40 KT NORTHERLY WINDS ADVECTING DRY AIR

TOWARD THE STORM.  LATER DROPSONDES SHOULD HELP DETERMINE HOW MUCH

OF THESE WINDS/DRY AIR ARE ACTUALLY REACHING THE CORE OF NADINE.

 

Drop 44 (former D45): 2303Z

Drop 45 (former D46): 2308Z

Drop 46 (Inserted Drop 46.1): 2313Z

IR (at 2245Z) and flight track (2313Z) screen capture as cross southern quadrants of Nadine (below):

 

Corresponding CPL (below) from flight track above:

 

Drop 47 (now back at original D47): 2318Z

2336Z: Brightness temperature product no longer indicates temperatures below -60C. Deepest clouds according to IR have rotated to southeast quadrant (have been rotating counterclockwise around the center all day). Still have not received salvo drops from center leg on MTS.

Now have center drops. Missed center to the north but 2117Z sonde indicates 60 kt at 900 mb and 2114Z indicates 65 kt just below 800 mb. All easterly winds.

Dropsonde from 2114Z below indicates 65 kt winds below 800 hPa in northeast quadrant

Drop 48: 2328Z

Drop 49: 2338Z

Drop 50: 2351Z

Drop 51: 0000Z

0000Z – Received a call from pilots that due to air traffic activity drops between HX01 and G10 will likely not be done. Wanted to be advised as to whether continue as planned or to proceed northward once reaching G11.

Drop 52: 0012Z

Drop 53: 0021Z

0045Z: Decision was made to proceed on north to south leg and eliminate the eastern part of the southern most west to east leg between HX01 and G10 and G10 back to G11. This was due to a window between 0100 and 0230Z in which ATC eliminated our ability to launch sondes. This change in tracked opened up 7 additional sondes. Flight plan was modified to now proceed north on the original longitude of 31 deg. West and proceed across the center (designated at 29.50N/31.0W) to 30.5N and proceed to do a box around the eye. The box will be 1x1 degree box around the center – clockwise around center.

1) 30.0 N 30.5 W

2) 29.5 N 30.5 W
3) 29.0 N 30.5 W
4) 29.0 N 31.0 W
5) 29.0 N 31.5 W
6) 29.5 N 31.5 W
7) 30.0 N 31.5 W

 

J. Sippel and M. Montgomery take over around this time

 

Drop 54: 0031Z

Drop 55: 0040Z

Drop 56: 0051Z

Drop 57: 0058Z

Drop 58: 0105Z

Drop 59: 0112Z

Drop 60: 0122Z

Drop 61: 0132Z

 

 

The following series of images and sondes correspond to the box around the eye that was made possible due to the cancellation of the segment of flight between G11 and G10 (ATC issues).

 

Tb overlaid with box pattern around Nadine eye – appx 0155 UTC 9/27.  Cloud top heights are appx 45kft according to CPL.

 

I think this is from the first E/W box leg south of eye

 

CPL from N/S leg of second box around eye

 

From SE turn

 

This shows a great comparison between estimated and actual CTH.  Blue/grn cutoff is 48 kft.  13km ~42.5 kft, 14 km ~46kft, so it appears the CTH product is overestimating.

 

As before except for CPL/Tb compare

 

Similar again.

 

Total of two circumnavigates + ¼, then to center.

 

Low-light camera clearly showed Cbs bubbling up along the flight path.  Unfortunately, not able to download image real-time.  Est max cloud tops

 

**drops in box pattern latlon in decimals**

Drop 62:0137 (30.0N/31W)

Drop 63: 0145 (30.0N/30.5W)

Drop 64: 0149 (29.5N/30.5W)

Drop 65: 0155 (29.0N/30.5W)

Drop 66: 0200 (29.0N/31.0W)

Drop 67: 0205 (29.0N/31.5W)

Drop 68: 0210 (29.5N/31.5W)

Drop 69: 0218 (30.0N/31.5W)

Drop 70: 0240 (29.0N/30.5W)

Drop 71: 0330 (29.5N/31.0W) (center drop)

Drop 72: 0344

Drop 73: 0401

Drop 74: 0418

Drop 75: 0429

 

Below: Center drop (61; ~29.5N/31.0W)

 

Below: Drop north of center (62; ~30.0N/31.0W)

 

Below: Drop of northeast box corner (63; ~30.0N/30.5W)

 

Below: Drop in convection east of center (64; ~29.5N/30.5W)

 

Below: Drop southeast corner in convection (65; 29.0N/30.5W)

 

Below: Drop south of center (66; 29.0N/31.0W)

 

Below: Drop southwest of center (67; 29.0N/31.5W)

 

Below: Drop west of center (68; 29.5N/31.5W)

 

Below: Drop northwest of center (69; 30.0N/31.5W)

 

Below: Drop southeast of center (70; 29.0N/30.5W)

 

Below: CENTER DROP (71):

 

A few high points: 

1. Max wind speed in free troposphere of 65 knots observed at ~21Z on 26 Sep around 850 mb, slightly northwest of the center (drop #29 (formerly drop 31): Drop identifier D2012...     112335069).

2. Max wind speed in boundary layer of 60 knots at ~21 Z (next drop) slightly below 900 mb, northwest of center

(drop #30 (formerly drop 32)).

3. For the 11 drops in the `center module' (square pattern with 60 nm sides) that was added tonight around 01Z (27Sep), 2 dropped out at 850 hPa or below, and 4 dropped out between 500 - 700 hPa. This is not a good success rate, but I am told that some of this data may be recoverable and some of these drop outs may be influenced by small pattern size and frequent turning of AV-6 in this pattern. Dry air evident down to as low as 700 hPa (with dew point depressions of ~20 - 30 C) down on the northwest side of 'center' pattern. Thanks to the moon's illumination of the clouds tonight, deep Cbs bubbling to approx. 45 - 47 kft and curved cloud bands were evident on the low-light camera onboard AV-6 as we flew around the center pattern.  (A spectacular sight.) 

4. Areas of dry air at 500 hPa and above (with similar dew point depressions) are also seen outside the 'core' of the storm. 

 

Questions remain about the environmental flow kinematics for this interesting tropical storm. For example, what is the source of the dry air near the center of circulation? If the source is the environmental air, what are the possible flow pathways into Nadine's pouch for this environmental dry air? The answer to both questions requires an examination of the Lagrangian flow boundaries and lack thereof surrounding Nadine. Some very preliminary insight into this issue is provided at: 

http://met.nps.edu/~mtmontgo/satanalatl2012/Thetaetracer48_loop.html

 

The animation (courtesy of Dr. Blake Rutherford, NRC post doc at NPS) shows the value of theta_e that parcels possessed at their location 2 days before, using a blend between the ECMWF analysis data (prior to 00Z) and forecast data (post 00Z). The loop suggests a strong tendency for the environmental dry air (with low theta_e below 325 K at 700 hPA) to wrap inwards towards Nadine's central region observed with AV-6. The tracer calculations use approx. 1 million Lagrangian particles and employ a layerwise flow approximation to obtain the tracer evolution. 

 

NHC mentioned the GH data again. Here is the discussion.

 

000
WTNT44 KNHC 270249
TCDAT4
 
TROPICAL STORM NADINE DISCUSSION NUMBER  58
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL142012
1100 PM AST WED SEP 26 2012
 
THE SATELLITE PRESENTATION OF NADINE HAS NOT CHANGED MUCH OVER THE
PAST SEVERAL HOURS.  DEEP CONVECTION REMAINS LIMITED TO A BAND
CURVING AROUND THE EASTERN SEMICIRCLE OF THE TROPICAL CYCLONE.
SATELLITE INTENSITY ESTIMATES FROM TAFB AND SAB...AS WELL AS
DROPSONDE DATA FROM THE NASA GLOBAL HAWK...SUPPORT HOLDING THE
INITIAL INTENSITY AT 45 KT. WHILE DRY AIR CONTINUES TO SURROUND
NADINE...THE TROPICAL STORM IS MOVING INTO AN AREA OF WARMER SEA
SURFACE TEMPERATURES...AND THE VERTICAL WIND SHEAR IS EXPECTED TO
REMAIN LIGHT ENOUGH TO ALLOW FOR SOME SLOW STRENGTHENING OVER THE
NEXT 36-48 HOURS. AFTER THAT...STRONGER SHEAR AND COOLER SEA
SURFACE TEMPERATURES SHOULD TO LEAD TO WEAKENING. THE NHC FORECAST
FOLLOWS THE LGEM MODEL AND IS CLOSE TO THE PREVIOUS ADVISORY.
 
NADINE CONTINUES TO MOVE TO THE SOUTHWEST AROUND A DEEP LAYER RIDGE
LOCATED OVER THE CENTRAL ATLANTIC...AND THE LONG-TERM MOTION
ESTIMATE IS 220/5. THE DYNAMICAL MODEL GUIDANCE REMAINS IN GOOD
AGREEMENT THAT NADINE WILL MOVE AROUND THE PERIPHERY OF THE RIDGE
FOR THE NEXT SEVERAL DAYS.  BY DAY 4...THE RIDGE IS EXPECTED TO MOVE
AWAY FROM THE TROPICAL CYCLONE...WHICH SHOULD RESULT IN FAIRLY WEAK
ENVIRONMENTAL STEERING CONDITIONS. THE MODEL SPREAD INCREASES
SUBSTANTIALLY AT THIS POINT...WITH THE GFS CONTINUING TO SUGGEST A
SLOW EASTWARD MOTION WHILE THE ECMWF SHOWS A TURN TOWARD THE
WEST OR SOUTHWEST. THE OFFICIAL FORECAST SPLITS THESE TWO
SOLUTIONS...AND LIES NEAR THE CONSENSUS MODELS IV15 AND FSSE.
 
THE WIND RADII WERE ADJUSTED BASED ON A 2338 ASCAT PASS.
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  27/0300Z 29.5N  31.4W   45 KT  50 MPH
 12H  27/1200Z 28.8N  32.2W   45 KT  50 MPH
 24H  28/0000Z 28.6N  33.6W   50 KT  60 MPH
 36H  28/1200Z 29.1N  34.8W   50 KT  60 MPH
 48H  29/0000Z 30.0N  35.8W   55 KT  65 MPH
 72H  30/0000Z 33.0N  36.8W   50 KT  60 MPH
 96H  01/0000Z 35.5N  37.5W   50 KT  60 MPH
120H  02/0000Z 36.0N  37.5W   45 KT  50 MPH
 
$$
FORECASTER AVILA/ZELINSKY

 

Meteosat image at 0930 UTC Sept 27 shows new convection near the center.  CIMSS color scale shows this convection having CTT ~ -65deg C.

 

Microwave composite from TRMM/TMI for 27 Sept 0246Z (SE sector) and 0423Z (NW sector) with OSCAT 0055Z (SE sector) showing box pattern location (during period 0140-0330Z) with N-S leg location relative to eyewall convective burst.

 

AV-6 landed back at WFF at 1150 UTC (7:50 am EDT).