Hurricane Harvey just got upgraded to a cat 3 storm:
He has been steadily getting stronger, which is more in line
with conditions, instead of sudden jumps. Currently he is at 27.2N, 96.4W,
heading NW at 10mph. Central pressure is 943mb and winds are an estimated
120mph, which actually makes him a mid-sized cat 3 storm. There are many
sources of local wind measurements in this area that we can look at to see what
the winds actually are. But he does have a decent eye, so I would agree that he
is definitely a solid strong cat 2 (cat 2 range: 96-110mph), possibly a weak
cat 3 (cat 3 range: 111-129mph). He does have some very good circulation at all
levels of the troposphere, which backs up the storm structure we see in the
imagery.
He is still on target for the Corpus Christi area of Texas, but there are a lot of thunderstorms and rain in this system to the north of there too - all the way to Louisiana - as we can see in the infrared image, where the red areas indicate the strongest storms - including tornados:
The major longer-term issue
is going to be water, as everyone is aware of already - storm surge and also
rainfall. This is compounded in Harvey's case because the forecast is for him
to stall over Texas, just inland, which will mean he will continue to dump some
rain in already soggy areas.
Looking at the storm surge from NOAA's Tides Online, the sea level is almost 3ft above normal at Corpus Cristi, where the winds are currently almost 50mph (weak Tropical Storm level at the moment):
But the air pressure is still
dropping (third chart), so the winds will continue to increase.
If we look off shore at the GCOOS website at a mooring that is close to the center of the storm, the winds are almost 60mph (26m/s = 58mph) (so we still see winds at Tropical Storm strength there too, but they are stronger):
And the air pressure is 981.5 mb, but is also still on that downward trend so the eye has not yet reached this location:
The other
place to look for winds are at the land-based NOAA National Weather Service
Stations, which are often at airports. From Corpus Christi airport at
just before 3pm CDT, the winds were 32mph and at South
Padre Island International Airport they
were 25mph. To see a good graphical representation, you can also look at
WillyWeather, which grabs the winds from those NOAA sites and plots them so you
can see a timeline... for Corpus Christi and South Padre Island International
Airport:
Before 3pm CDT, these two locations were not
quite at Tropical Storm strength.
From all of these sources of data, you can begin
to build a picture of the winds from inland (airports) to coast (Tides Online)
to offshore (GCOOS) as the storm is approaching, with the best indicators of
what is to come from the offshore data of course.
The other place I like to look at are NOAA's NWS radars, just because you can see the storm
approaching and get a better idea of the local rainfall... for Hurricane
Harvey:
Unfortunately the NWS have not yet switched away
from Adobe Flash, which is no longer supported in many places (was it because
of security issues?), so you may not be able to see the loop video-style
imagery directly from their site. But from this, you can see the eye and also
that there is a strong band of rain (yellow) right along the coastline there.
Ok, that's it
for now. I will try and jump on later with an update on the data side!
Good luck out
there!
J.
Blogs archived at http://jyotikastorms.blogspot.com/
Twitter @JyovianStorm
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DISCLAIMER: These remarks are just what I think/see regarding tropical storms - not the opinion of any organization I represent. If you are making an evacuation decision, please heed your local emergency management and the National Hurricane Center's official forecast and the National Weather Service announcements. This is not an official forecast. If I "run away, run away" (Monty Python), I'll let you know.
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