ATL: ANDREA - Advisories

[cycloneye]

BULLETIN
Tropical Storm Andrea Advisory Number 1
NWS National Hurricane Center Miami FL AL012025
1100 AM AST Tue Jun 24 2025

...ANDREA BECOMES THE FIRST TROPICAL STORM OF THE SEASON IN THE
ATLANTIC...


SUMMARY OF 1100 AM AST...1500 UTC...INFORMATION
-----------------------------------------------
LOCATION...36.6N 48.9W
ABOUT 1205 MI...1940 KM W OF THE AZORES
MAXIMUM SUSTAINED WINDS...40 MPH...65 KM/H
PRESENT MOVEMENT...ENE OR 60 DEGREES AT 17 MPH...28 KM/H
MINIMUM CENTRAL PRESSURE...1014 MB...29.95 INCHES



Tropical Storm Andrea Discussion Number 1
NWS National Hurricane Center Miami FL AL012025
1100 AM AST Tue Jun 24 2025

The area of low pressure between Bermuda and the Azores that we have
been monitoring for a few days (90L) developed persistent deep
convection overnight. This is shown by the latest subjective Dvorak
current intensity estimate from TAFB of 2.0, and the current
wind estimate of 35 kt is supported by the past several
scatterometer passes showing 30 to 35 knot winds. Even though deep
convection is now decreasing, due to the persistent convection
overnight and pulsing convection over the past 36 hours, the system
has met the criteria of being classified as a tropical storm, albeit
a marginal one, making Tropical Storm Andrea the first Atlantic
storm of the year.

The initial motion is 060/15 knots. This motion is expected to
continue through dissipation, which is forecast to occur by 36
hours. The track forecast closely follows the TVCA and HCCA
consensus guidance.

Andrea will be a short-lived tropical storm, as environmental
conditions will become increasingly hostile over the next day or
so. Water temperatures will plummet to around 21/22C, with vertical
wind shear increasing to 35-40 knots, in a dry mid-level
environment. The intensity forecast holds Andrea at tropical storm
strength today, with the system weakening into a post-tropical
remnant low by Wednesday morning because of the cold waters and
dissipating shortly thereafter.


FORECAST POSITIONS AND MAX WINDS

INIT 24/1500Z 36.6N 48.9W 35 KT 40 MPH
12H 25/0000Z 37.9N 46.3W 35 KT 40 MPH
24H 25/1200Z 39.6N 41.5W 30 KT 35 MPH...POST-TROP/REMNT LOW
36H 26/0000Z...DISSIPATED

$$
Forecaster Jelsema/Blake/Hagen

[cycloneye]

BULLETIN
Tropical Storm Andrea Advisory Number 2
NWS National Hurricane Center Miami FL AL012025
500 PM AST Tue Jun 24 2025

...ANDREA EXPECTED TO BECOME A POST-TROPICAL REMNANT LOW LATER
TONIGHT...


SUMMARY OF 500 PM AST...2100 UTC...INFORMATION
----------------------------------------------
LOCATION...37.9N 47.4W
ABOUT 1110 MI...1785 KM W OF THE AZORES
MAXIMUM SUSTAINED WINDS...40 MPH...65 KM/H
PRESENT MOVEMENT...NE OR 50 DEGREES AT 20 MPH...31 KM/H
MINIMUM CENTRAL PRESSURE...1015 MB...29.98 INCHES



Tropical Storm Andrea Discussion Number 2
NWS National Hurricane Center Miami FL AL012025
500 PM AST Tue Jun 24 2025

Deep convection associated with Andrea collapsed around 1500Z and
has not redeveloped. The latest subjective Dvorak current intensity
estimate from TAFB was 1.5, which is in line with the degradation
in satellite presentation. Scatterometer data from earlier
this morning showed numerous 33 to 36 knot wind barbs, so the
initial intensity for this advisory is held at 35 knots.

The initial motion is 050/17 knots. This motion is expected to
continue through dissipation, which is forecast to occur by 24
hours. The track forecast closely follows the latest consensus
guidance.

The clock is ticking on Andrea now with the loss of deep convection.
This will be a short-lived tropical storm, as environmental
conditions will become increasingly hostile during the next 12 to 24
hours. Water temperatures will drop to around 20/21C, with vertical
wind shear increasing to 30-40 knots, in a dry mid-level
environment. The intensity forecast shows Andrea becoming a
post-tropical remnant low later tonight, with the system expected to
dissipate on Wednesday.


FORECAST POSITIONS AND MAX WINDS

INIT 24/2100Z 37.9N 47.4W 35 KT 40 MPH
12H 25/0600Z 39.0N 44.5W 30 KT 35 MPH...POST-TROP/REMNT LOW
24H 25/1800Z...DISSIPATED

$$
Forecaster Jelsema/Blake

[cycloneye]

BULLETIN
Post-Tropical Cyclone Andrea Advisory Number 3
NWS National Hurricane Center Miami FL AL012025
1100 PM AST Tue Jun 24 2025

...ANDREA BECOMES A REMNANT LOW...
...THIS IS THE FINAL ADVISORY...


SUMMARY OF 1100 PM AST...0300 UTC...INFORMATION
-----------------------------------------------
LOCATION...38.7N 45.2W
ABOUT 985 MI...1585 KM W OF THE AZORES
MAXIMUM SUSTAINED WINDS...35 MPH...55 KM/H
PRESENT MOVEMENT...ENE OR 60 DEGREES AT 20 MPH...31 KM/H
MINIMUM CENTRAL PRESSURE...1015 MB...29.98 INCHES

Post-Tropical Cyclone Andrea Discussion Number 3
NWS National Hurricane Center Miami FL AL012025
1100 PM AST Tue Jun 24 2025

Andrea is now a remnant low. The system has lacked deep convection
since earlier this morning and is unlikely to redevelop any while
traversing increasingly cold sea-surface temperatures, strong
northeasterly vertical wind shear, and very dry mid-level air.
Therefore, this will be the final advisory on Andrea. Scatterometer
data received after the last advisory also indicates winds have
decreased to about 30 kt. The remnant low should continue to spin
down, with the various global and regional model guidance showing
the circulation opening up into a surface trough in about 24 hours.

The initial motion is 060/17 kt. This motion is expected to continue
until the remnant low dissipates. Additional information on this
system can be found in High Seas Forecasts issued by the National
Weather Service, under AWIPS header NFDHSFAT1, WMO header FZNT01
KWBC, and online at ocean.weather.gov/shtml/NFDHSFAT1.php


FORECAST POSITIONS AND MAX WINDS

INIT 25/0300Z 38.7N 45.2W 30 KT 35 MPH...POST-TROP/REMNT LOW
12H 25/1200Z 40.1N 41.1W 25 KT 30 MPH...POST-TROP/REMNT LOW
24H 26/0000Z...DISSIPATED

$$
Forecaster Papin