Skip Navigation Links
NOAA NOAA United States Department of Commerce

Hurricane IOTA

Hurricane Iota Discussion Number  12
NWS National Hurricane Center Miami FL       AL312020
400 AM EST Mon Nov 16 2020
Iota has explosively deepened 26 mb during the past 6 hours and has 
rapidly intensified an incredible 35 kt during that same time. An 
Air Force Reserve reconnaissance aircraft and aircrew that flew the 
arduous, 10-hour round-trip mission into Iota reported a maximum 
700-mb flight-level wind speed of 134 kt and peak SFMR surface winds 
of 121 kt, which supports the initial intensity of 125 kt, making 
Iota a strong Category 4 hurricane. Furthermore, the pressure fell 
an amazing 10 mb from 945 mb down to 935 mb in a little over an hour 
between those two fixes. The crew also encountered intense lightning 
and hail in the southwestern quadrant, where recent remote data 
indicate that frequent lightning is still occurring. The aircrew 
reported that the eye was around 15 n mi wide, and the latest 
GOES-16 hi-resolution infrared satellite imagery confirms that the 
eye diameter, and that the eye has cleared out with continued 
warming eye temperatures and cooling surrounding cloud tops.

Iota is moving north of due west, or 280/09 kt.  A westward to 
west-northwestward motion is forecast until powerful Hurricane Iota 
makes landfall in northeastern Nicaragua later tonight. Shortly 
after landfall, a building ridge to the north of the hurricane is 
expected to nudge Iota on a more westward track through 36 hours, 
followed by a slower west-southwestward motion across central and 
southwestern Honduras until it dissipates in the 72-96 hour 
period. The latest model guidance remains tightly clustered. The 
new NHC track forecast is very similar to the previous advisory 
track, and lies close to a blend of the consensus track models TVCN, 
Iota is expected to remain in environmental conditions characterized 
by near-zero vertical wind shear, SSTs near 29 deg C, and a moist 
mid-level environment. The combination of these factors plus the 
relatively small radius of maximum winds (RMW) of about 10 n mi, 
argues for continued rapid strengthening right up until landfall 
occurs, and Iota could be near Category 5 strength at that time. 
After landfall, rapid weakening is expected over the rugged terrain 
of Nicaragua and Honduras. Iota is forecast to become a tropical 
storm by 36 hours, and degenerate into a post-tropical remnant low 
by 60 hours, if not sooner, which is in line with the SHIPS 
intensity inland decay model. The NHC official intensity forecast 
remains above of all of the available guidance through 24 hours, and 
then closely follows the Decay-SHIPS intensity model thereafter.
Key Messages:
1.  Iota is expected to continue to rapidly intensify and could 
possibly be a catastrophic category 5 hurricane when it approaches 
the coast of Central America tonight. Extreme winds and a 
life-threatening storm surge are expected along portions of the 
coast of northeastern Nicaragua and eastern Honduras, where a 
hurricane warning is in effect.
2.  Hurricane conditions and storm surge impacts are likely on 
Providencia today.  Tropical storm conditions are expected and 
hurricane conditions are possible on San Andres.
3.  Through Thursday, heavy rainfall from Iota will likely lead to 
life-threatening flash flooding and river flooding across portions 
of Central America. Flooding and mudslides in Honduras and Nicaragua 
could be exacerbated by Hurricane Eta’s recent effects there, 
resulting in significant to potentially catastrophic impacts.
INIT  16/0900Z 13.6N  81.1W  125 KT 145 MPH
 12H  16/1800Z 13.8N  82.2W  135 KT 155 MPH
 24H  17/0600Z 14.1N  83.7W  120 KT 140 MPH...INLAND
 36H  17/1800Z 14.3N  85.2W   55 KT  65 MPH...INLAND
 48H  18/0600Z 14.3N  86.8W   35 KT  40 MPH...INLAND
 60H  18/1800Z 14.1N  88.3W   20 KT  25 MPH...POST-TROP/INLAND
 72H  19/0600Z 13.8N  89.7W   20 KT  25 MPH...POST-TROP/INLAND
 96H  20/0600Z...DISSIPATED
Forecaster Stewart