ATL: IRMA - Post-Tropical - Discussion

[Kingarabian]

[Aric Dunn]

Radar from the plane. its has a very large eye for its size.. its must have gone through a ERC at somepoint while the satellite appearance was lacking.. should shee this deepen soon.

http://tropicalatlantic.com/recon/recon ... Center.kmz

[otowntiger]

this is down at 17.4N. It's resumed a good WSW motion

why did it go wnw like that for a little bit? and also is it possible for it to occur again?

Maybe a bit north of due west, but it didn't look like WNW to me. In any extent, that was simply a trochoidal wobble.
I think a few Twitter posts got a little too caught up in its significance.

AJC3: how concerned are you for a possible significant impact here in central Florida at this time?

[Chris_in_Tampa]

Through 5:51pm EDT

[GCANE]

7C Core temp at 10K ft


Product: NOAA Vortex Message (URNT12 KWBC)
Transmitted: 3rd day of the month at 21:44Z
Agency: National Oceanic and Atmospheric Administration (NOAA)
Aircraft: Lockheed WP-3D Orion (Reg. Num. N42RF)
Storm Number & Year: 11 in 2017
Storm Name: Irma (flight in the North Atlantic basin)
Mission Number: 1
Observation Number: 06 ( See all messages of this type for this mission. )
A. Time of Center Fix: 3rd day of the month at 21:26:12Z
B. Center Fix Coordinates: 17°23'N 49°52'W (17.3833N 49.8667W)
B. Center Fix Location: 713 statute miles (1,148 km) to the ENE (66°) from Bridgetown, Barbados.
C. Minimum Height at Standard Level: 2,764m (9,068ft) at 700mb
D. Estimated (by SFMR or visually) Maximum Surface Wind Inbound: 79kts (~ 90.9mph)
E. Location of the Estimated Maximum Surface Wind Inbound: 11 nautical miles (13 statute miles) to the WSW (253°) of center fix
F. Maximum Flight Level Wind Inbound: From 332° at 87kts (From the NNW at ~ 100.1mph)
G. Location of Maximum Flight Level Wind Inbound: 11 nautical miles (13 statute miles) to the WSW (253°) of center fix
H. Minimum Sea Level Pressure: 961mb (28.38 inHg)
I. Maximum Flight Level Temp & Pressure Altitude Outside Eye: 11°C (52°F) at a pressure alt. of 3,044m (9,987ft)
J. Maximum Flight Level Temp & Pressure Altitude Inside Eye: 18°C (64°F) at a pressure alt. of 3,001m (9,846ft)
K. Dewpoint Temp (collected at same location as temp inside eye): 12°C (54°F)
K. Sea Surface Temp (collected at same location as temp inside eye): Not Available
L. Eye Character: Open in the west, W
M. Eye Shape & Diameter: Circular with a diameter of 30 nautical miles (35 statute miles)
N. Fix Determined By: Penetration, Radar, Wind, Pressure and Temperature
N. Fix Level: 700mb
O. Navigational Fix Accuracy: 0.02 nautical miles
O. Meteorological Accuracy: 1 nautical mile

Remarks Section:
Maximum Flight Level Outbound and Flight Level Wind: 96kts (~ 110.5mph) which was observed 17 nautical miles (20 statute miles) to the NNE (33°) from the flight level center at 21:30:11Z
Dropsonde Surface Wind at Center: From 185° at 11kts (From the S at 13mph)

[psyclone]

It's still way too soon for legit speculation on CONUS impacts.

[Aric Dunn]

if this motion keeps up its going to go south of the next forecast point without any problems..

[GCANE]

[NJWxHurricane]

It's still way too soon for legit speculation on CONUS impacts.

this

[KWT]

of course recon will confirm.. but on satellite it appears to have sagged a little more to the SW the last hour or so.. almost to 17n already.. if it gets down to 16 to 16.5 then PR is in the crosshairs

Yea the whole system appears to have stair-stepped down somewhat again after that WNW wobble briefly earlier on.

Doesn't seem to be looking as good as it did but clearly as the eye seems to have gotten masked again. Eventually once it does stop getting forced WSW it should start to get a very good presentation, especially as it should now be hitting warmer waters.

Also not too surprising this is actually at 115mph.

[Extratropical94]

[Extratropical94]

URNT15 KWBC 032201
NOAA2 0111A IRMA HDOB 17 20170903
215130 1853N 04856W 6951 03203 0067 +103 +070 115046 046 035 002 00
215200 1855N 04855W 6952 03201 0070 +101 +067 120046 046 036 002 00
215230 1857N 04855W 6952 03200 0069 +102 +065 122045 046 038 000 03
215300 1859N 04857W 6952 03200 0071 +101 +059 120046 047 037 002 03
215330 1859N 04859W 6952 03201 0080 +095 +069 118046 046 039 002 00
215400 1900N 04902W 6952 03201 0080 +094 +078 117047 047 039 002 00
215430 1900N 04904W 6951 03204 0084 +091 +078 116046 047 039 002 00
215500 1900N 04907W 6952 03201 0079 +094 +073 112048 048 038 002 00
215530 1900N 04910W 6953 03201 0080 +093 +075 109049 050 038 002 00
215600 1901N 04912W 6951 03204 0083 +092 +075 108049 049 038 002 00
215630 1901N 04915W 6952 03201 0078 +096 +069 107049 050 040 002 00
215700 1901N 04918W 6952 03200 0073 +100 +061 106050 051 039 001 00
215730 1901N 04920W 6953 03198 0074 +098 +062 105050 051 038 001 00
215800 1901N 04923W 6952 03202 0075 +097 +072 106047 048 038 001 00
215830 1901N 04925W 6952 03200 0067 +103 +061 107048 048 038 001 00
215900 1901N 04928W 6953 03196 0061 +109 +053 105048 049 038 002 00
215930 1902N 04931W 6952 03201 0064 +108 +052 106049 050 038 001 00
220000 1902N 04933W 6951 03201 0071 +102 +058 103049 049 037 001 00
220030 1902N 04936W 6951 03201 0071 +101 +056 102050 051 036 001 00
220100 1902N 04939W 6952 03200 0071 +101 +058 102050 051 036 001 00

[CrazyC83]

Based on that dropsonde, the pressure is 960mb right now. A bit deeper than first thought.

[Kingarabian]

[cycloneye]

[AJC3]

why did it go wnw like that for a little bit? and also is it possible for it to occur again?

Maybe a bit north of due west, but it didn't look like WNW to me. In any extent, that was simply a trochoidal wobble.
I think a few Twitter posts got a little too caught up in its significance.

AJC3: how concerned are you for a possible significant impact here in central Florida at this time?

Obviously we need to pay close attention, but it won't be known for several more days how serious the threat will eventually be.
A lot of equally plausible options are still on the table. Still about a week away from any potential impact.

[Extratropical94]

[Extratropical94]

URNT15 KWBC 032211
NOAA2 0111A IRMA HDOB 18 20170903
220130 1902N 04941W 6952 03201 0073 +098 +066 102051 051 036 002 00
220200 1902N 04944W 6952 03200 0071 +100 +066 100051 051 036 001 00
220230 1902N 04946W 6952 03199 0073 +098 +069 100050 050 035 001 00
220300 1902N 04949W 6952 03200 0074 +097 +072 098050 050 036 001 00
220330 1902N 04952W 6952 03199 0073 +097 +072 096050 050 035 001 00
220400 1902N 04954W 6950 03203 0067 +105 +055 094046 047 037 000 00
220430 1902N 04957W 6952 03200 0067 +104 +056 094045 046 036 001 00
220500 1902N 05000W 6952 03201 0060 +108 +071 094046 047 036 001 00
220530 1902N 05002W 6952 03200 0061 +111 +032 094045 045 037 001 00
220600 1903N 05005W 6952 03200 0063 +110 +034 094045 046 037 001 00
220630 1903N 05007W 6952 03200 0063 +109 +038 095046 046 037 001 00
220700 1903N 05010W 6952 03201 0064 +108 +048 096045 046 034 001 00
220730 1903N 05013W 6952 03200 0065 +106 +057 096046 046 035 001 00
220800 1903N 05015W 6952 03201 0065 +108 +050 093046 046 035 001 00
220830 1903N 05018W 6951 03203 0066 +108 +045 091045 045 035 001 00
220900 1903N 05021W 6952 03203 0064 +110 +042 088046 046 034 001 00
220930 1903N 05023W 6951 03205 0061 +113 +042 086046 046 033 002 00
221000 1903N 05026W 6952 03203 0058 +118 +020 084046 047 035 002 00
221030 1903N 05028W 6952 03203 0056 +119 +016 084047 047 035 002 00
221100 1903N 05031W 6952 03202 0056 +119 +014 083048 048 035 001 00

[Kingarabian]

[Extratropical94]