03/623 AM.
A major and long lasting heat wave is expected to persist through all of next week with dangerously hot temperatures. Clouds and dense fog are expected portions of the coastal waters this morning, likely reoccuring again tonight into Sunday morning.
(tdy-Mon), 03/941 AM.
***UPDATE***
Temperatures are soaring already this morning with the biggest upswings from yesterday being everywhere north of LA County. This is thanks to a nearly -4 offshore gradient that is the driver of the hot temps at the coast. It's already 88 in Oxnard as 0930, up 13 degrees from yesterday at this time. So a very hot day today, and with the expectation that this heat wave will be with us most of the next week. One possible ray of hope is that the offshore gradient will slowly be weakening through the the week, allowing at least a slight cooling trend for coastal areas (1-2 degrees each day). But valleys and intermediate areas (Downtown LA and similar) will likely not have much of a cooling trend.
***From Previous Discussion***
Expecting most areas to remain clear overnight, although marine layer clouds have pushed into a few areas along the Central Coast, and any fog that forms may become dense at times, as the marine layer is quite shallow. Low confidence in the coverage of marine layer clouds this morning, and cannot fully rule out clouds reaching the southern Santa Barbara coast to the Ventura County Coast.
High pressure will persist over the region in the short-term supporting ongoing hot weather for southern California. By Sunday a weak upper level low off the coast will bring more southerly flow to the region this weekend. Monday, upper level flow will weaken significantly as the high builds off the coast, transitioning southern California into more northerly upper level flow. Offshore pressure gradients (LAX-DAG and LAX- BFL) appear to peak today and Sunday around 2-3 mb, with gradient strengths shifting to favor more a more easterly component rather than northerly. Still, winds should remain below advisory levels. Northern Santa Barbara County, and SLO County will see some warming today (thanks to a slight increase in offshore flow). Extreme Heat Warnings will continue to be in effect through the weekend and the majority of next week, along with Heat Advisories starting today for SLO and the northern SBA Counties. Based on the latest forecast trends that advisory will likely need to be extended at least another day or two.
(Tue-Fri), 03/420 AM.
Hot weather will drag on from Tuesday into Thursday as high pressure persists. However, offshore pressure gradients are forecast to weaken Wednesday through Friday, with coastal sea breezes likely returning Thursday, growing stronger Friday (onshore LAX- DAG gradient reaching around 3 mb). Saturday, models indicates approaching tropical moisture along with an upper level trough, leading to cooling temperatures and increased clouds for the weekend. This may even open the door for showers as early as late Sunday.
03/1734z.
At 1614Z at KLAX, there was no marine layer. There was a very weak surfaced based inversion with a top at 1300 ft and a temp of 31 C.
High confidence in VFR TAFs for all sites except for KSBP & KSMX. Chances of V/LIFR conds between 04/08Z-16Z: KSBP/KSMX (15%).
KLAX, High confidence in VFR TAF. E-SE wind should shift W around 03/20Z (+/- 1hr). East wind component likely a touch stronger tomorrow morning peaking 04/12Z-18Z nearing 7-8kts.
KBUR, High confidence in VFR TAF. No wind issues expected.
03/719 AM.
Generally quiet conditions expected across the coastal waters through the forecast period. Localized Small Craft Advisory (SCA) gusts may occur each afternoon and evening between Point Conception and San Nicolas Island, off the coast of Point Dume, and across the San Pedro Channel.
Ca, Extreme Heat Warning in effect until 8 PM PDT Thursday for zones 38-87-88-349>358-362-366>375-548-550. (See LAXNPWLOX). Heat Advisory in effect until 8 PM PDT Sunday for zones 341>345-347-348. (See LAXNPWLOX). PZ, NONE.
