All Eyes on Hurricane Joaquin

HURRICANE JOAQUIN

As of the 11 p.m. EDT update from the National Hurricane Center, Hurricane Joaquin has rapidly intensified and is now a MAJOR CATEGORY THREE hurricane with sustained winds of 115 mph and gusts as high as 140 mph. A hurricane is considered major when sustained surface winds exceed 110 mph. Joaquin is forecast to strengthen further to category 4 strength as early as tomorrow (Thursday) afternoon/evening with sustained winds of over 140 mph and gusts as high as 165 mph. The image below is Joaquin's latest official forecast track from the National Hurricane Center. It is important not to get caught up on the center track, but rather focus on the entire area shaded within the bold white lines. That area is known as the cone of uncertainty. The majority of the computer models, including the GFS (American forecast model) show Joaquin crashing into the eastern seaboard...the latest run of the GFS model sends Joaquin crashing into the North Carolina/Virginia coast during the wee hours of Sunday. There is still a lot of uncertainty on where Joaquin is going to make landfall, or if it even will do so. I write that, because the ECMWF, or European forecast model, another very important and generally very reliable model, takes Joaquin away from the east coast of the United States and out to sea. Regardless, heavy rainfall and potential flooding possible along the east coast over the coming days in response to a frontal system and an upper level low unrelated to Joaquin. If Joaquin decides to slam into the east coast, moisture/rain associated with the hurricane will only add insult to injury to the east coast flood threat. No doubt all eyes will be on Joaquin over the coming days. (Areas shaded in red are under a HURRICANE WARNING, that includes a good chunk of The Bahamas) where conditions will be deteriorating quickly as Joaquin approaches tonight into Thursday. You can keep up with all of the latest information and updates on Hurricane Joaquin at this link:  http://www.nhc.noaa.gov/

National Hurricane Center Forecast Track (as of 10 p.m. CDT Wednesday)

National Hurricane Center's 10 p.m. Forecast Discussion on Hurricane Joaquin:
(The following is expert analysis and contains a lot of meteorological jargon...scroll down to "KEY MESSAGES" if you wish to read a simplified and more to the point analysis)

HURRICANE JOAQUIN DISCUSSION NUMBER  13
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL112015
1100 PM EDT WED SEP 30 2015

Joaquin has rapidly intensified during the past 24 hours with the
satellite presentation continuing to improve this evening.  The eye
has recently become apparent near the center of the very symmetric
central dense overcast.  An Air Force Reserve Hurricane Hunter
aircraft that has been investigating the hurricane this evening has
measured peak 700 mb flight-level winds of 113 kt and 102 kt surface
winds from the SFMR.  These data support an initial intensity of
100 kt, making Joaquin the second major hurricane of the 2015
Atlantic hurricane season. NOTE: Communications problems have
delayed the public release of the Air Force reconnaissance data.

Joaquin continues to move slowly southwestward with an initial
motion estimate of 220/5 kt.  The hurricane is forecast to move
slowly southwestward or west-southwestward for another 24 hours or
so while it remains to the south of a narrow northeast to southwest
oriented ridge.  This ridge is expected to weaken by Friday as a
trough deepens and cuts off over the southeastern United States.
This should cause Joaquin to turn northward within 48 hours. The 18Z
runs of the GFS and HWRF remain in general agreement with the 12Z
UKMET and Canadian models moving Joaquin around the northeastern
portion of the cut-off low and bring the hurricane inland over the
Carolinas or mid-Atlantic states.  The 12Z ECMWF remains the outlier
by showing a track toward the northeast out to sea.  The NHC
forecast continues to follow the trend of the bulk of the guidance
and takes Joaquin toward the U.S east coast. The NHC track is
similar to the previous advisory and is once again east of the
multi-model consensus.  The NOAA G-IV aircraft has recently
completed its synoptic surveillance flight, and data collected
during this mission should be assimilated into the 0000 UTC models,
hopefully reducing the spread of the track guidance.

The upper-level wind pattern over the hurricane is forecast by the
global models to become even more conducive during the next couple
of days.  This favors additional intensification, with the only
possible limiting factors being upwelling of cool SSTs beneath the
slow-moving hurricane and eyewall cycles which could cause some
fluctuations in intensity.  By 72 hours, increasing southwesterly
shear, dry air intrusion, and lower SSTs are expected to cause
gradual weakening.  The updated NHC intensity forecast has been
significantly increased from the previous advisory primarily due to
the higher initial intensity. The official forecast is between the
lower statistical guidance and the higher HWRF during the first
36-48 hours, and is near the SHIPS/LGEM guidance after that time.


KEY MESSAGES:

1.  Preparations to protect life and property within the warning
areas in the Central Bahamas should be completed now.

2.  Confidence in the details of the forecast after 72 hours remains
low, since we have one normally excellent model that keeps Joaquin
far away from the United States east coast.   The range of possible
outcomes is still large, and includes the possibility of a major
hurricane landfall in the Carolinas.

3.  Every effort is being made to provide the forecast models with
as much data as possible.  The NOAA G-IV jet has begun a series of
missions in the storm environment, and the National Weather Service
has begun launching extra balloon soundings.

4.  Because landfall, if it occurs, is still more than three days
away, it's too early to talk about specific wind, rain, or surge
impacts from Joaquin in the United States.  Regardless of Joaquin's
track, strong onshore winds will create minor to moderate coastal
flooding along the coasts of the mid-Atlantic and northeastern
states through the weekend.

5.  A hurricane watch for a portion of the U.S. coast could be
required as early as Thursday evening.

6. Many portions of the eastern U.S. are currently experiencing
heavy rains and gusty winds associated with a frontal system. These
heavy rains are likely to continue for the next few days, even if
the center of Joaquin stays offshore.  The resulting inland flood
potential could complicate preparations for Joaquin should it head
toward the coast, and even more substantial inland flooding is
possible if Joaquin later passes near or over these same areas.

What's Steering Joaquin???

A deepening or strengthening trough, or line, of low pressure in the mid levels of the atmosphere and a blocking ridge of high pressure over the northern Atlantic will work together to steer Joaquin from its current position east of The Bahamas north towards the eastern seaboard. This should begin to take place over the coming days as low pressure deepens over the southeastern United States. Remember, air flows counter-clockwise into an area of low pressure in the northern hemisphere...the south-southeasterly wind flow ahead of the low pressure system will help to steer Joaquin north. See image below.

GFS 18z 30 September 2015 Valid 12z Saturday October 03 2015
***This is just a snapshot of what one forecast model believes is going to happen...newer model runs just coming in now are painting a different picture. Models will continue to change over the coming days***

South Central Texas Weather Update

The temperature soared to 95°F this afternoon in Austin missing the record high of 97°F set back in 1923 by two degrees. A weak and poorly-defined frontal boundary is working its way across the state. Behind the front, a significantly drier and slightly cooler air mass will be moving into the area over the coming days on northerly winds aloft and at the surface behind this boundary. Noticeably drier and slightly cooler for this upcoming weekend with highs closer to average for this time of year in the mid to upper 80s. With that dry air in place, mornings and evenings will feel especially great. Low temperatures in out-lying low-lying areas will drop into the mid to upper 50s with lower 60s expected within the Austin area. Slowly, but surely our weather pattern is going to be taking a turn for the better, and by better I mean cooler. Enjoy!