Hurricane Arthur

[TropicalAnalystwx13]

Product: Air Force Vortex Message (URNT12 KNHC)
Transmitted: 3rd day of the month at 17:15Z
Aircraft: Air Force Aircraft (Last 3 digits of the tail number are 301)
Storm Number & Year: 01L in 2014
Storm Name: Arthur (flight in the North Atlantic basin)
Mission Number: 11
Observation Number: 14
A. Time of Center Fix: 3rd day of the month at 17:00:30Z
B. Center Fix Coordinates: 32°42'N 78°24'W (32.7N 78.4W)
B. Center Fix Location: 92 miles (149 km) to the E (94°) from Charleston, SC, USA.
C. Minimum Height at Standard Level: 2,918m (9,573ft) at 700mb
D. Estimated (by SFMR or visually) Maximum Surface Wind: 63kts (~ 72.5mph)
E. Location of the Estimated Maximum Surface Wind: 19 nautical miles (22 statute miles) to the NW (306°) of center fix
F. Maximum Flight Level Wind Inbound: From 33° at 50kts (From the NNE at ~ 57.5mph)
G. Location of Maximum Flight Level Wind Inbound: 21 nautical miles (24 statute miles) to the NW (305°) of center fix
H. Minimum Sea Level Pressure: 980mb (28.94 inHg)
I. Maximum Flight Level Temp & Pressure Altitude Outside Eye: 8°C (46°F) at a pressure alt. of 3,047m (9,997ft)
J. Maximum Flight Level Temp & Pressure Altitude Inside Eye: 13°C (55°F) at a pressure alt. of 3,048m (10,000ft)
K. Dewpoint Temp & Sea Surface Temp (collected at same location as temp inside eye): Not Available
L. Eye Character: Open in the northwest
M. Eye Shape & Diameter: Circular with a diameter of 28 nautical miles (32 statute miles)
N. Fix Determined By: Penetration, Radar, Wind, Pressure and Temperature
N. Fix Levels (sfc and flt lvl centers are within 5nm of each other): Surface and 700mb
O. Navigational Fix Accuracy: 0.02 nautical miles
O. Meteorological Accuracy: 1 nautical mile
Remarks Section:
Maximum Outbound and Flight Level Wind: 84kts (~ 96.7mph) which was observed 17 nautical miles (20 statute miles) to the SE (131°) from the flight level center at 17:05:30Z
Maximum Flight Level Temp: 13°C (55°F) which was observed 11 nautical miles (13 statute miles) to the NW (313°) from the flight level center

[Brick Tamland]

[phil882]

100 knot winds @ 970 hPa in the eyewall... not too far above the surface.

Level	Wind Direction	Wind Speed
987mb (Surface)	200° (from the SSW)	58 knots (67 mph)
982mb	200° (from the SSW)	63 knots (72 mph)
977mb	205° (from the SSW)	85 knots (98 mph)
972mb	205° (from the SSW)	97 knots (112 mph)
970mb	210° (from the SSW)	100 knots (115 mph)
951mb	220° (from the SW)	94 knots (108 mph)
925mb	225° (from the SW)	92 knots (106 mph)
911mb	225° (from the SW)	85 knots (98 mph)
892mb	225° (from the SW)	87 knots (100 mph)
850mb	225° (from the SW)	79 knots (91 mph)
809mb	225° (from the SW)	69 knots (79 mph)
697mb	235° (from the SW)	82 knots (94 mph)

[chris87]

 

Category 3 winds @ 970 hPa in the eyewall... not too far above the surface.

Level	Wind Direction	Wind Speed
987mb (Surface)	200° (from the SSW)	58 knots (67 mph)
982mb	200° (from the SSW)	63 knots (72 mph)
977mb	205° (from the SSW)	85 knots (98 mph)
972mb	205° (from the SSW)	97 knots (112 mph)
970mb	210° (from the SSW)	100 knots (115 mph)
951mb	220° (from the SW)	94 knots (108 mph)
925mb	225° (from the SW)	92 knots (106 mph)
911mb	225° (from the SW)	85 knots (98 mph)
892mb	225° (from the SW)	87 knots (100 mph)
850mb	225° (from the SW)	79 knots (91 mph)
809mb	225° (from the SW)	69 knots (79 mph)
697mb	235° (from the SW)	82 knots (94 mph)

 

pretty misleading to use a scale used for surface winds to "categorize" winds well above the friction (surface) layer 

[phil882]

pretty misleading to use a scale used for surface winds to "categorize" winds well above the friction (surface) layer 

 

This just just the raw dropsonde data... yea 970 hPa is likely up above the PBL, but its certainly possible to get those sort of winds mixing down in gusts in the eyewall. 

 

EDIT: I fixed the wording... should have been clear it was just 100 knot winds aloft.

[PSUBlizzicane2007]

This just just the raw dropsonde data... yea 970 hPa is likely up above the PBL, but its certainly possible to get those sort of winds mixing down in gusts in the eyewall.

Well yes of course higher gusts will mix in any time, but there is no evidence to suggest that this storm is above 75 KT in categorical 1-minute sustained winds which is generous in and of itself.

[chris87]

This just just the raw dropsonde data... yea 970 hPa is likely up above the PBL, but its certainly possible to get those sort of winds mixing down in gusts in the eyewall. 

 

 

Well yes of course higher gusts will mix in any time, but there is no evidence to suggest that this storm is above 75 KT which is generous in and of itself.

 

sure you can mix down -- but throwing around sensationalized language like "Category 3" winds when you're now even referring to surface winds is misleading -- you have to always assume someone might take you seriously

[Amped]

Well yes of course higher gusts will mix in any time, but there is no evidence to suggest that this storm is above 75 KT in categorical 1-minute sustained winds which is generous in and of itself.

You sound like you're from jtwc or jma.

[Jayhawkers]

FWIW the SPC did give the TOR watch 60/40 probs... Even mentioning the possibility of a couple intense tornadoes...

[Brick Tamland]

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 390
NWS STORM PREDICTION CENTER NORMAN OK
125 PM EDT THU JUL 3 2014

THE NWS STORM PREDICTION CENTER HAS ISSUED A

* TORNADO WATCH FOR PORTIONS OF
COASTAL NORTH CAROLINA
COASTAL WATERS

* EFFECTIVE THIS THURSDAY AFTERNOON AND FRIDAY MORNING FROM 125
PM UNTIL 200 AM EDT.

* PRIMARY THREATS INCLUDE...
A FEW TORNADOES LIKELY WITH A COUPLE INTENSE TORNADOES POSSIBLE
ISOLATED SIGNIFICANT DAMAGING WIND GUSTS TO 75 MPH POSSIBLE

THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 30 STATUTE
MILES EITHER SIDE OF A LINE FROM 25 MILES WEST SOUTHWEST OF
WILMINGTON NORTH CAROLINA TO 40 MILES NORTH NORTHEAST OF CAPE
HATTERAS NORTH CAROLINA. FOR A COMPLETE DEPICTION OF THE WATCH
SEE THE ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU0).

PRECAUTIONARY/PREPAREDNESS ACTIONS...

REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR
TORNADOES AND SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH
AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR
THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS
AND POSSIBLE WARNINGS.

&&

OTHER WATCH INFORMATION...CONTINUE...WW 389...

DISCUSSION...RISK FOR SCTD SMALL SUPERCELLS WITH LOW-LVL
MESOCYCLONES/POTENTIAL TORNADOES EXPECTED TO INCREASE THIS AFTN
THROUGH TNGT ALONG THE NC CST AS REGION IS GLANCED BY FAVORABLE NE
QUADRANT OF HRCN ARTHUR. AS THE HRCN CONTINUES NNEWD...ENVELOPE OF
DEEPER/MORE MOISTURE-RICH
WILL OVERSPREAD THE CST IN CONJUNCTION WITH THE MOST
STRONGLY-SHEARED LOW-LVL WIND FIELD. GIVEN EXISTING DEGREE OF
LOW-LVL INSTABILITY ON NRN AND ERN SIDES OF ARTHUR /PER LIGHTNING
STRIKES/...CONVERGENT FLOW MAY CONTINUE TO SPAWN SHOWERS/STORMS
CAPABLE OF WATERSPOUTS/TORNADOES.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 0.5 INCH. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 65 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
400. MEAN STORM MOTION VECTOR 16045.


 

[WxJordan]

Video I captured just before 1:00 p.m. at Oak Island, NC. Conditions are continuing to go down hill rapidly. Pressure is dropping and winds are increasing.

[Minnesota Meso]

[phil882]

Well yes of course higher gusts will mix in any time, but there is no evidence to suggest that this storm is above 75 KT in categorical 1-minute sustained winds which is generous in and of itself.

 

Well recon really hasn't gone through any of the mesovorticies rotating around in the eyewall... there is a really intense mesovort in the NE eyewall right now as seen on velocity which is showing 100+ knots on the base velocity. Now the beam height is around 1.9 km above the ground here, but I'd bet there are some impressive surface winds beyond what the recon has identified thus far within that feature. Hopefully recon will be able to sample it when it does another NE-SW pass (before it rotates out of the eastern quadrant)

 

 

sure you can mix down -- but throwing around sensationalized language like "Category 3" winds when you're now even referring to surface winds is misleading -- you have to always assume someone might take you seriously

 

Fair enough... I should have referred to the 970 hPa level being around 200-300 meters off the ground. 

[TropicalAnalystwx13]

Satellite presentation has improved dramatically over the past few frames. Recon finding 75-80kt flight-level winds well removed from the center on the east side.

 

[Thundersnow12]

[downeastnc]

This buoy should be pretty much ground zero so we can see how well it is mixing winds to the surface...

 

http://www.ndbc.noaa.gov/station_page.php?station=41037

[SN_Lover]

Satellite presentation has improved dramatically over the past few frames. Recon finding 75-80kt flight-level winds well removed from the center on the east side.

 

I don't see how this is in any way weakening. Looks like it might be getting ready for a RI cycle. Eye is rapidly clearing. 

 

[Thundersnow12]

Radar bins on velocity data continue to get stronger in the NE eye wall. 

[AJF0602]

Looking at the above image the first thing that came to mind was Hurricane Fran, I have a hour or 2 before my weather rapidly deteriorates.

[PSUBlizzicane2007]

I don't see how this is in any way weakening. Looks like it might be getting ready for a RI cycle. Eye is rapidly clearing.

No one said it is weakening. Recon reports so far have just shown it to not be as strong as was estimated, and to generally be leveling off in intensity. Another NE/SW pass is coming up so maybe it will show something different.

Remember Recon evidence >> *

[gulfcane]

 

eye spy with my brand new eye....NC!

[phil882]

No one said it is weakening. Recon reports so far have just shown it to not be as strong as was estimated, and to generally be leveling off in intensity. Another NE/SW pass is coming up so maybe it will show something different.

Remember Recon evidence >> *

 

The only problem is that recon only flies in a small sliver of the actual TC. Radar derived velocity data has its error bars, but they generally utilized quite frequently by the NHC as a storm approaches landfall. 

[klw]

The only problem is that recon only flies in a small sliver of the actual TC. Radar derived velocity data has its error bars, but they generally utilized quite frequently by the NHC as a storm approaches landfall.

 

Also enjoy this recon mission while you can, because it will likely be the last one before landfall. The next mission is weirdly not scheduled to make a fix until tomorrow at 06 UTC. The storm will probably be making landfall before then. 

It seems odd that they would not be flying constant missions with a storm this close to the coast and possibly intensifying.

[PSUBlizzicane2007]

A slight improvement to 82 KT in the SFMR readings, but FL winds are pretty much the same (82 KT vs. 84 KT earlier). Pressure trending down ever so slightly now which is a good sign that it worked out the dry air, but I'm just afraid Arthur is going to run out of time before it makes landfall in NC.

[N. OF PIKE]

Did euro bring this west ? i.e over east NC then close to cape cod. Only see 48 hr point close to east end of maine

[KPITSnow]

The only problem is that recon only flies in a small sliver of the actual TC. Radar derived velocity data has its error bars, but they generally utilized quite frequently by the NHC as a storm approaches landfall.

Also enjoy this recon mission while you can, because it will likely be the last one before landfall. The next mission is weirdly not scheduled to make a fix until tomorrow at 06 UTC. The storm will probably be making landfall before then.

Thanks for stating this, as I was wondering if this was true.

[Weathergun]

NE Quad 82kt FL wind and 82kt SFMR report with just a 13mm/hr rainfall rate:

83430 3314N 07748W 6966 03039 9919 +096 +060 147079 080 061 006 00183500 3313N 07750W 6966 03025 9906 +094 +078 146077 079 064 010 00183530 3312N 07751W 6966 03015 9896 +092 +090 141079 082 069 020 00183600 3310N 07752W 6970 02993 9879 +097 +096 140072 077 072 042 00183630 3309N 07754W 6974 02973 9864 +106 +106 155054 068 081 030 00183700 3308N 07755W 6961 02982 9843 +109 //// 164047 050 082 013 01

[dan88]

The only problem is that recon only flies in a small sliver of the actual TC. Radar derived velocity data has its error bars, but they generally utilized quite frequently by the NHC as a storm approaches landfall.

 

Also enjoy this recon mission while you can, because it will likely be the last one before landfall. The next mission is weirdly not scheduled to make a fix until tomorrow at 06 UTC. The storm will probably be making landfall before then. 

 

 

Something happened to this mission planned to begin at 5:30pm?

FLIGHT FOUR -- TEAL 71A. 04/0000,0300,0600ZB. AFXXX 1401A ARTHURC. 03/2130ZD. 33.5N 76.8WE. 03/2345Z TO 04/0600ZF. SFC TO 10,000 FT

[Srain]

Structurally, Arthur has improve rather significantly over the past hour and a half.

 

 

[PSUBlizzicane2007]

The only problem is that recon only flies in a small sliver of the actual TC. Radar derived velocity data has its error bars, but they generally utilized quite frequently by the NHC as a storm approaches landfall.

Also enjoy this recon mission while you can, because it will likely be the last one before landfall. The next mission is weirdly not scheduled to make a fix until tomorrow at 06 UTC. The storm will probably be making landfall before then.

With the pressure being more or less steady state, and flight level winds in multiple passes now being the same... It's starting to look like holding onto threads when claiming that this is going to intensify much further before landfall. Maybe 5, possibly but unlikely 10 if it can really get going... But there is just not much time.