5pm AST Tuesday: Ophelia model guidance closer to Azores
Posted by Chris in Tampa on 10/10/2017, 6:21 pm
It's forecast to become a hurricane. Some models are closer to the Azores, but the NHC is leaning more toward the Euro which is further away from the islands.

Track:
http://www.nhc.noaa.gov/refresh/graphics_at2+shtml/?cone#contents

Floater:
http://www.ssd.noaa.gov/PS/TROP/floaters/17L/17L_floater.html
Wider Atlantic views: http://www.ssd.noaa.gov/PS/TROP/trop-atl.html

Models:
http://hurricanecity.com/models/models.cgi?basin=al&year=2017&storm=17&display=google_map&latestrun=1

Euro:
https://www.tropicaltidbits.com/analysis/models/?model=ecmwf&region=atl&pkg=z500_mslp

GFS:
https://www.tropicaltidbits.com/analysis/models/?model=gfs&region=atl&pkg=z500_mslp






Tropical Storm Ophelia Discussion Number   7
NWS National Hurricane Center Miami FL       AL172017
500 PM AST Tue Oct 10 2017

The overall convective structure of Ophelia has improved markedly
over the past several, including the development of numerous,
tightly curved bands and a burst of deep convection near the center.
Upper-level anticyclonic outflow has also increased and expanded in
all quadrants. Dvorak satellite current intensity estimates are
T3.5/55 kt from TAFB and T4.0/65 kt from SAB, so the initial
intensity has been conservatively increased to 50 kt. A 28-30 kt
wind report from ship PBQL, located more 200 nmi northwest of the
center, indicates that the outer circulation is also strengthening.

The initial motion estimate is 135/04 kt. Ophelia is forecast to
continue moving southeastward at a slow but steady pace for the next
48 hours or so while the cyclone remains embedded within a broad
mid-/upper-level trough. The NHC model guidance remains in good
agreement on the Ophelia beginning to lift out to the northeast by
72 h, and then gradually accelerate into the mid-latitude westerlies
ahead of an eastward-moving mid-tropospheric trough. The latest
model guidance remains tightly packed, but it has also shifted
northward, which brings Ophelia closer to the Azores in the 96-120
hour period. However, the new forecast track was not shifted
northward and remains along the southern edge of the guidance
envelope between the NOAA HCCA consensus model and the more
southerly ECMWF model.


The GFS and ECMWF models continue to forecast only modest
intensification for the next 48-72 hours, despite the vertical wind
shear being fairly low at less than 10 kt. However, those models are
forecasting more vigorous strengthening after 96 h as Ophelia
experiences some baroclinic interaction, especially by 120 hours.
The strong baroclinic deepening on day 5 could be overdone somewhat
given that the best jetstream dynamics are forecast to be about 300
nmi northwest of the surface low and frontal zone. For now, the
official intensity forecast remains similar to the previous
advisory, and is little lower than the intensity consensus models
HCCA and IVCN and the GFS and ECMWF solutions on days 4 and 5.

FORECAST POSITIONS AND MAX WINDS

INIT  10/2100Z 31.1N  38.0W   50 KT  60 MPH
12H  11/0600Z 30.6N  37.5W   55 KT  65 MPH
24H  11/1800Z 30.2N  36.8W   60 KT  70 MPH
36H  12/0600Z 30.2N  36.4W   65 KT  75 MPH
48H  12/1800Z 30.5N  35.6W   70 KT  80 MPH
72H  13/1800Z 32.0N  32.2W   70 KT  80 MPH
96H  14/1800Z 34.7N  25.8W   70 KT  80 MPH
120H  15/1800Z 39.0N  17.0W   70 KT  80 MPH...POST-TROP/EXTRATROP

$$
Forecaster Stewart







Tropical Storm Ophelia Advisory Number   7
NWS National Hurricane Center Miami FL       AL172017
500 PM AST Tue Oct 10 2017

...OPHELIA STRENGTHENS A LITTLE OVER THE FAR EASTERN ATLANTIC...
...EXPECTED TO BECOME A HURRICANE BY THURSDAY...


SUMMARY OF 500 PM AST...2100 UTC...INFORMATION
----------------------------------------------
LOCATION...31.1N 38.0W
ABOUT 785 MI...1265 KM SW OF THE AZORES
MAXIMUM SUSTAINED WINDS...60 MPH...95 KM/H
PRESENT MOVEMENT...SE OR 135 DEGREES AT 6 MPH...9 KM/H
MINIMUM CENTRAL PRESSURE...1001 MB...29.56 INCHES


WATCHES AND WARNINGS
--------------------
There are no coastal watches or warnings in effect.


DISCUSSION AND 48-HOUR OUTLOOK
------------------------------
At 500 PM AST (2100 UTC), the center of Tropical Storm Ophelia was
located near latitude 31.1 North, longitude 38.0 West. Ophelia is
moving toward the southeast near 6 mph (9 km/h) and this general
motion is expected to continue during the next day or two.

Maximum sustained winds have increased to near 60 mph (95 km/h) with
higher gusts. Additional strengthening is forecast during the next
48 hours, and Ophelia is expected to become a hurricane by Thursday.

Tropical-storm-force winds extend outward up to 70 miles (110 km)
from the center.

The estimated minimum central pressure is 1001 mb (29.56 inches).


HAZARDS AFFECTING LAND
----------------------
None.


NEXT ADVISORY
-------------
Next complete advisory at 1100 PM AST.

$$
Forecaster Stewart
216
In this thread:
5pm AST Tuesday: Ophelia model guidance closer to Azores - Chris in Tampa, 10/10/2017, 7:21 pm
< Return to the front page of the: message board | monthly archive this page is in
Post A Reply
This thread has been archived and can no longer receive replies.