https://www.nhc.noaa.gov/data/tcr/AL152017_Maria.pdf...Maria’s peak intensity of 150 kt is based on a blend of SFMR-observed surface winds of
152 kt and 700-mb flight-level winds of 157 kt. Maria’s 65-kt intensity increase over 24 h on 18
September makes it tied for the sixth-fastest intensifying hurricane in the Atlantic basin record.
The intensity of the hurricane when it struck Dominica, 145 kt, is based on an SFMRobserved
surface wind of 152 kt which, based on quality control by data processing software, is
believed to be somewhat inflated, and a maximum 10-min wind of 130 kt measured at Douglas-Charles Airport on the island, which conservatively corresponds to a 1-min wind of 143 kt. Maria
is the strongest hurricane on record to make landfall on Dominica (or strike within 60 n mi of that
island).
Maria’s minimum central pressure of 908 mb is based on an eye dropsonde measurement
by the Air Force Hurricane Hunters of 910 mb with 23-kt winds at the surface at 0313 UTC 20
September. This is the lowest pressure on record of any hurricane in the Atlantic basin east of
70°W, and breaks the record that had been set just a couple of weeks earlier by Irma of 914 mb.
The landfall intensity of the cyclone in Puerto Rico, 135 kt, is based on an extrapolation of
the weakening trend noted in the aircraft data after the eyewall replacement began several hours
earlier. There were no believable Doppler-derived winds from the San Juan WSR-88D radar that
supported a higher intensity. It should be noted, however, that in Puerto Rico, winds of category
5 intensity were almost certainly felt at some elevated locations on the island.
The landfall pressures of the hurricane in Dominica and Puerto Rico of 922 and 920 mb,
respectively, are based on an extrapolation of the system’s deepening and filling trends before
making landfall in those islands. Several storm chasers observed pressures higher than the
estimated minimum value in Puerto Rico, but these observers were not thought to be in the exact
center of the hurricane. Maria is the strongest hurricane to make landfall in Puerto Rico since a
category 5 hurricane in 1928 (known as Segundo San Felipe).
Maria’s eyewall replacement early on 20 September resulted in roughly a tripling of its eye
diameter, from 9 n mi to about 28 n mi, prior to landfall in Puerto Rico. This event was likely a
major contributor to weakening, but also increased the areal exposure of the island to the
hurricane’s highest winds....
... heavier rainfall occurred in Puerto Rico, where one location had a storm total of
nearly 38 inches (Fig. 8). River discharges at many locations in the island were at record or nearrecord
levels. Severe flooding and mud slides affected most of the island, with the most significant
flooding associated with the La Plata River....
...The NOAA estimate of damage in
Puerto Rico and the U.S. Virgin Islands due to Maria is 90 billion dollars, with a 90% confidence
range of +/-$25.0 billion, or $65.0-$115.0 billion, which makes Maria the third costliest hurricane
in U.S. history, behind Katrina (2005) and Harvey (2017). Maria is by far the most destructive
hurricane to hit Puerto Rico in modern times, as the previous costliest hurricane on record for the
island was Georges in 1998, which in 2017 dollars “only†caused about 5 billion dollars of damage....
