Posted: 5:00 pm Friday, October 6th, 2017
By Kirk Mellish
It’s a tropical storm now but NHC forecast strengthening to a minimal 80 mph hurricane CAT 1 before making landfall late Saturday night or early Sunday morning in SE Louisiana and Southern Mississippi.
The models are in good agreement on the track, which has been shifted slightly east and sped up, but future intensity is highly uncertain due to competing and conflicting influences.
The greatest risk for downed trees and power loss in some spots is in the mountains and far North and West suburbs. This reminds me of a flip of Irma… instead of worst I-85 south and east then, this time it’s worst near or NW of I-85. Although the max winds look LOWER for Nate, at least as of now.
Remember the intensity of these storms often change rapidly up or down with little or no warning and with only modest forecast skill.
Our weather in Atlanta and the rest of Georgia will go downhill over the weekend and into Monday, but details can still change for the worse or better. My forecast is online at wsbradio.com and on the radio with frequent updates through the weekend! And on Twitter. Scroll down for more.
STORM SURGE WARNING:
Satellite imagery this afternoon indicates that convection
associated with Nate is becoming better organized, with a strong
convective band now wrapping about three-quarters of the way around
the center. Recent data from NOAA buoy 42056 near the center
suggest the central pressure has fallen to near 993 mb, and the
buoy just reported a 1-minute average wind of 49 kt. Based on
this, the initial intensity is increased to a possibly conservative
50 kt. The next aircraft investigating Nate is scheduled to arrive
The initial motion is north-northwestward or 340/18 kt. Nate
remains between a complex deep-layer low pressure area over the
western Gulf of Mexico and Central America and a building ridge of
high pressure over the western Atlantic. This combination should
steer the storm quickly north-northwestward for the next 24 h or so.
After that, Nate should turn northward and northeastward as it goes
around the western edge of the ridge and recurves into the
mid-latitude westerlies. The guidance remains in good agreement
with the direction of motion, and it has come into better agreement
on the speed. Thus, the new forecast track is similar to, but
slightly to the west of the the previous track, and it calls for the
center of Nate to pass near or over the northeastern tip of the
Yucatan Peninsula in about 6 h, followed by landfall on the northern
Gulf Coast around the 36-h point. It should be noted that the
ECMWF and GFS are both a little to the left of the current track.
Conditions appear favorable for continued strengthening up to
landfall on the northern Gulf Coast, and Nate is expected to make
landfall there as a hurricane. The new intensity forecast, which is
an update of the previous one, lies near the upper edge of the
intensity guidance. Given the current developments, there is still
a possibility of a period of rapid intensification as Nate crosses
the Gulf of Mexico. As alternative scenarios to the actual forecast
of steady strengthening, the ECMWF forecasts no additional
strengthening as Nate crosses the Gulf of Mexico, and the GFS/UKMET
forecast little additional strengthening until the last 12 h before
3-DAY RAINFALL TOTALS ON AVERAGE Saturday-Monday PM:
ECMWF MODEL WIND GUST ESTIMATE 8pm Sunday-11am Monday:
FOLLOW ME on Twitter @MellishMeterWSB.