UPDATE: ACTIVATION starting this afternoon at 3pm PST on K6MPN and N6NFI Repeaters

February 18, 2024 admin

Starting at 3pm PST Sunday afternoon, 02/18/2024, the SF Bay Area Skywarn group will be activated. I will be monitoring the K6MPN repeater (444.500 MHz, +5.0 MHz offset, PL=100Hz CTCSS tone) and the N6NFI repeater (145.230 MHz, -0.600 MHz offset, PL=100Hz CTCSS tone) for severe weather and storm damage reports through Tuesday morning at least. Please keep in mind that we are SECONDARY users on the K6MPN repeater, which is a primary resource for the South County Amateur Radio Emergency Service (SCARES) group.

There are multiple alerts in effect for the SF Bay Area issued by the NWS WFO in Monterey, CA. See sfoskywarn.org/alerts for details. See https://poweroutage.us/area/state/california for current power outages in CA, listed by county.

Please email photos showing storm related damage or flooding to ckolovson – at – gmail.com.

Stay safe!
73, Curt Kolovson W6RQ
SF Bay Area Skywarn Coordinator

Quoting from today’s AFD:

.SHORT TERM...
(This evening through Monday night)
Issued at 122 PM PST Sun Feb 18 2024

Current radar showing rain showers increasing in coverage as the
warm front approaches the coast this afternoon. Evident on radar
and visible satellite, the cold front follows close behind as a
cold occlusion sets up offshore north of the Bay Area going into
this evening. The eastward movement of these features and further
destabilization due to cold air advection aloft should result in
increasing rain rates over the next few hours. Heading into the
evening hours once the warm front moves over the Central Coast and
the cold front nears the coast, it is expected that rainfall rates
will further increase, especially for orographically enhanced
areas from the Santa Cruz Mtns southward. Areas of 0.5-0.6 inches
per hour appear likely along the Big Sur Coast, Santa Lucia, and
Santa Cruz Mtns late this evening, persisting for a longer period
over the Santa Lucia, where rainfall rates could approach up to 1
inch per hour in isolated areas. This has prompted the issuance of
a Flash Flood Watch for the River Fire burn scar for the
possibility of debris flows, mudslides, and flash flooding in the
burn scar area and low-lying areas along the Carmel River near the
burn scar. As we move into the overnight period, further
destabilization occurs with additional cooling aloft creating a
more favorable environment for thunderstorms. At the moment, it
appears that the initial threat will be for areas more near the
coast and the North Bay during the overnight period. A widespread
break in the rainfall appears likely Monday morning as the
initial wave pushes through further east into the state. This
opens the door for the second wave of rainfall later Monday
morning where a greater likelihood for thunderstorms exists over
a larger area. Current thunderstorm-related threats include gusty
winds and lightning, and a slight threat for waterspouts along the
coast. High res guidance has been relatively consistent at
depicting a line of heavier showers and thunderstorms training
into the Bay Area Monday afternoon. Should this be the case, we
could end up with isolated locations along the peninsula and East
Bay that end up with a bit more rainfall than expected. However,
these such features are notoriously difficult to nail down, so
will keep that in the back pocket as a low possibility for now.

Current best forecast for rainfall amounts is on the order of
2-3.5" across the North Bay, 1.75-2.5" for the SF Peninsula, 1-2"
for lower elevations of rainshadowed valleys (Santa Clara,
Salinas, East Bay, Southern Monterey Bay), 3-5" Santa Cruz Mtns,
and 3-6" for the Big Sur Coast with isolated areas of 8-9" in the
Santa Lucia.

In terms of wind, current observations show the ballpark to be
about 25-35 mph across the area as of this early afternoon. Expect
these winds to continue into tonight and through Monday afternoon.
Once the cold front nears the area this evening, expect gusts to
increase generally into the 35-45 mph range, with isolated gusts
to 50 mph along the coast and 60 mph along ridgetops. These gusts
will lessen a bit overnight before increasing again with the next
wave of rain and thunderstorms Monday morning.