Pismo Beach Ocean / Surf Report
9/23/2020
SEA/SWELL:
Increasing northwesterly winds off the California coastline
will generate a 4- to 6-foot northwesterly (310-degree, deep-
water) sea and swell (with a 5- to 11-second period) today
through Thursday morning.
A Gulf of Alaska storm will generate a 7- to 9-foot northwesterly
(305-degree, deep-water) sea and swell (with a 6- to 17-second
period) on Thursday afternoon and night, peaking at 8 to 10 feet
(with a 6- to 16-second period Friday. This northwesterly sea
and swell will decrease to 7 to 9 feet (with a 7- to 14-second
period) on Saturday.
This sea and swell will become a 6- to 8-foot northwesterly
(300-degree, deep-water) swell (with an 8- to 11-second period)
on Sunday, decreasing to 4 to 6 feet (with an 8- to 10-second
period) on Monday through Tuesday.
Arriving from the Southern Hemisphere:
Today's 1- to 3-foot Southern Hemisphere (215-degree, deep-water)
swell (with a 15- to 17-second period) will remain at this
height but with a gradually shorter period through Thursday.
A 1- to 2-foot Southern Hemisphere (210-degree, deep-water)
swell (with a 21- to 23-second period) will arrive along our
coastline on Sunday, increasing to 2- to 3-feet (with an 18-
to 20-second period) on Monday through Tuesday.
ATMOSPHERIC CONDITIONS:
Gentle to moderate (8 to 18 mph) Santa Lucia (northeasterly)
winds this morning, followed by fresh to strong (19 to 31 mph)
northwesterly winds this afternoon will continue to
produce mostly clear skies. These Santa Lucia winds will also
create warmer temperatures with the beaches reaching the 70s,
the coastal valleys the 80s, and inland valleys the 90s today
and tomorrow.
Note: A cold front will produce rain in far Northern California
tonight into Thursday morning. This low pressure system
will be dry when it reaches the Central Coast later on
Thursday.
A ridge of high pressure will build across the West Coast later
on Thursday and is forecast to reach 592 dm by Saturday. Over
this period, moderate to fresh (13 to 24 mph) Santa Lucia
(northeasterly) winds are expected during the morning and
warmer temperatures throughout the Central Coast. High
temperatures are forecast climb to triple-digit levels in
the coastal and inland valleys and 80s along the beaches
by Saturday.
Gentle to moderate (8 to 18 mph) variable winds are forecast on
Sunday through Tuesday, which will allow the marine layer to
redevelop along the coastline and bring cooler temperatures to
the beaches. Away from the immediate coastline, the early-
autumn heat wave will continue to produce widespread high 90s
to low 100s in the coastal and inland valleys on Sunday
through Tuesday.
Temperatures will start to drop off next Wednesday, Thursday
and Friday as the upper-level high-pressure ridge responsible
for the autumn heat wave starts to break down and strong to
gale-force (25 to 38 mph) northwesterly winds develop along
the coastline.
WILDFIRE INDEX RATINGS:
COASTAL: FIA 508
INLAND: FIA 497, 510, 575, 580, 582 and 590
The PG&E Fire Index Ratings will be at high (R3) levels
along the Coastline and very high (R4) levels in the
Coastal and Inland Valleys and Far Inland Areas today
and Thursday.
The PG&E Fire Index Ratings will be at very high (R4)
levels along the Coastline, Coastal and Inland Valleys,
and Far Inland Areas on Friday.
DIABLO CANYON METEOROLOGICAL TOWER TEMPERATURE DATA:
Yesterday's Today's Tomorrow's
Min Max Min Max Min Max
53.4° 56.8° 53.1° 70.0° 57.0° 76.0°
PG&E Weather Office in San Francisco predicted temperatures
for San Luis Obispo County
Inland Temperatures, Paso Robles
Actual Predicted
Tue Wed Thu Fri Sat Sun Mon Tue Wed
49 96 51 97 52 94 50 91 48 100 50 103 53 105 53 104 58 101
Coastal Valleys Temperatures, San Luis Obispo
Tue Wed Thu Fri Sat Sun Mon Tue Wed
53 77 53 86 55 87 56 90 54 100 57 96 59 98 58 96 60 91
WINDS:
Fresh to strong (19 to 31 mph) northwesterly winds will develop
this afternoon, decreasing and shifting out of the north tonight.
A pattern of moderate to fresh (13 to 24 mph) Santa Lucia
(northeasterly) winds during morning, shifting out of the
northwest and increasing to strong to gale-force (25 to 38 mph)
levels during afternoon will start Thursday and will continue
through Saturday.
Gentle to moderate (8 to 18 mph) variable winds are forecast on
Sunday through Tuesday, increasing out of the northwest next
Wednesday and Thursday.
DIABLO CANYON METEOROLOGICAL TOWER WIND DATA:
Today's Maximum Winds:
Max peak winds: NE 7.0 mph @ 8:45 a.m.
Max sustained wind: NE 5.0 mph @ 8:45 a.m.
Yesterday's Maximum Winds:
Max peak winds: NW 23.0 mph @ 6:30 p.m.
Max sustained wind: NW 17.0 mph @ 6:30 p.m.
SEAWATER TEMPERATURES:
Seawater temperatures will range between 55 and 58 degrees
through today, decreasing to 53 to 56 degrees on Thursday
through Monday.
OCEAN CURRENTS:
A southerly (offshore) flowing current is forecast to continue
to flow southward through Monday.
SEAWATER VISIBILITY:
Seawater visibility was 19 to 21 feet at the Diablo Canyon Marina.
==========================================================================
24-Hour Ocean Condition Outlook for Wednesday 09/23 to Thursday 09/24
SEA/SWELL: DIR. NW HT. 4-6 PER. 5-11 This morning
Remaining at: DIR. NW HT. 4-6 PER. 5-11 This afternoon
Remaining at: DIR. NW HT. 4-6 PER. 5-11 Tonight
(Combined with: DIR. S HT. 1-3 PER. 15-17 All day)
WINDS: DIR. NW SPEED 5-10 This morning
Increasing to: DIR. NW SPEED 20-25 + 30 This afternoon
Decreasing to: DIR. N SPEED 5-10 Tonight
==========================================================================
48-Hour Ocean Condition Outlook for Thursday 09/24 to Friday 09/25
SEA/SWELL: DIR. NW HT. 4-6 PER. 5-11 Thursday morning
Increasing to: DIR. NW HT. 7-9 PER. 6-17 Thursday afternoon
Remaining at: DIR. NW HT. 7-9 PER. 6-16 Thursday night
(Combined with: DIR. S HT. 1-3 PER. 14-16 All day Thursday)
WINDS: DIR. NE SPEED 10-15 + 25 Thursday morning
Increasing to: DIR. NW SPEED 25-30 + 35 Thursday afternoon
Decreasing to: DIR. N SPEED 10-15 Thursday night
==========================================================================
Extended Ocean Condition Outlook:
The northwesterly winds will decrease on Sunday through Tuesday.
==========================================================================
