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Flooding in the Mississippi Valley; Fire Weather in California; Tropical Cyclone Rafael

A cold front will stall near the Mississippi River Valley today with excessive rainfall bringing areas of flooding over parts of the region. Gusty winds and dry conditions will drive critical to extremely critical fire weather over portions of central and southern California through Thursday. Tropical Storm Watches have been issued for parts of the Florida Keys ahead of Tropical Cyclone Rafael. Read More >



...EF-1 TORNADO CONFIRMED IN MONKTON MARYLAND...

Date...Friday, April 26, 2019
Estimated Time...319 to 323 PM EDT
Maximum EF-Scale Rating...EF-1
Estimated Maximum Wind Speed...90 MPH
Maximum Path Width...150 Yards
Path Length...3 miles
Beginning Lat/Lon...39.5647 N/76.6103 W
Ending Lat/Lon...39.5934 N/76.5695 W
* Fatalities...0
* Injuries...0

...Summary...
A storm survey was conducted by staff of the National Weather Service
Baltimore/Washington Weather Forecast Office in Sterling, Virginia,
of damage resulting from a storm that occurred between 319 and 323
PM EDT on Friday, April 26, 2019, in Monkton, Maryland.

The survey confirmed that an EF-1 tornado began at 319 PM EDT on
Corbett Road between Monkton Farms Drive and Falls Road, and ended
at 323 PM EDT near the intersection of Shepperd Road and MD-562/138
Troyer Road, resulting in intermittent damage mainly to softwood
trees. This time was estimated from rotational velocity signatures
evident on both KLWX Sterling National Weather Service Weather
Surveillance Radar (88D) and TBWI FAA Terminal Doppler Weather
Radar. Several area residents noted sudden, chaotic winds around
320 PM EDT. No concentrated or tornadic damage was found southwest
or northeast of this location, although there was sporadic tree
damage concluded to be from straight line winds throughout much of
northeastern Baltimore County into northwestern Harford County.

Most of the damage was to softwood (pine) trees. On Corbett Road,
two softwood (pine) trees were snapped a third of the way up on
the west side of the road, and fell toward the northeast. Across
the street in a wooded area, a third tree (hardwood, birch)
snapped halfway up and fell toward the east. A fourth tree
(softwood, pine) just to the north snapped halfway up, and fell
toward the south. The pattern of the tree damage was convergent
in nature, implying a circulation reached the surface at this
point. Other leaf and small branch debris was noted in the area.
The damage was confined to a 100-yard wide path at this location.

The tornado continued northeastward with a forward speed of 40 to
50 mph (estimated from TBWI radar), reaching the 2400 block of
Monkton Road at 320 PM EDT. At this location, four pine trees
snapped about halfway up, and fell toward the northeast; one small
tree along the southeast side of the path snapped at the base and
fell toward the southwest; two other pine trees snapped halfway
up and fell toward the north or northwest. There were also
numerous large limbs scattered around this area. Damage was
confined to a path that expanded slightly in width to about 125
yards.

The circulation reached JM Pearce Road just east of MD-138
Shepperd Road at 321 PM EDT. At least ten trees were snapped in a
150-yard wide path here. Three trees on the northwest side of the
path fell toward the south or southeast, with the rest falling
toward the northwest to northeast. All of the trees that fell were
softwoods (mainly pines).

At 322 PM, the tornado reached MD-138 Shepperd Road in the 2900
block. Over a dozen trees were snapped between the base and
halfway up here. Additionally, half a dozen trees were topped. The
trees that were snapped closer to the base were along and
southeast of the roadway, and fell facing the northwest, north and
northeast. The trees that had their tops snapped off were along
the north side of the road, and blew south across the road onto
adjacent properties. A house at a horse barn had two screens blown
in toward the northeast, and the slide of a swing set on the
property was torn off and blew toward the northwest. Steel barns
on the property sustained no notable damage, and no shingles or
siding were removed from the house.

The last instance of tornadic damage was noted at the intersection
of Shepperd Road and MD-562/138 Troyer Road. Several softwood
trees were snapped here, as well, facing southwest, south and
southeast.

Residents in the area noted chaotic, sudden winds which lasted
very briefly around 320 PM, and also noted the haphazard nature of
the tree falls on their property (as opposed to everything
blowing in one direction).

Given the intermittent tree damage (snapped trees), and the fact
that very little if any structural damage was noted, it is
concluded that maximum wind speeds were 80 to 90 MPH. Above this
speed is when most sturdy structures start sustaining notable
damage, like substantial loss of shingles or siding, which was NOT
noted anywhere along the path.

We would like to extend our appreciation to area residents and
county emergency management for helping coordinate and provide
information for this survey.

EF Scale: The Enhanced Fujita Scale classifies tornadoes into the
following categories:

EF0...Weak......65 to 85 mph
EF1...Weak......86 to 110 mph
EF2...Strong....111 to 135 mph
EF3...Strong....136 to 165 mph
EF4...Violent...166 to 200 mph
EF5...Violent...>200 mph

The information in this statement is preliminary and subject to
change pending final review of the event and publication in NWS
Storm Data.