27/144 PM.
Hotter than normal conditions will continue for the foreseeable future. Slight cooling is possible through Thursday, with heat increasing again Friday through Sunday. The hot and humid conditions during the day and night will bring elevated risks of heat-related illness.
(tdy-Thu), 27/144 PM.
Widespread MODERATE TO HIGH heat risk is very likely to return Friday into the weekend. Now is the time to start socializing this threat with your community and family and consider rescheduling activities that might but you or your loved ones at risk. Have a plan to stay cool, especially if work or other activities take you outside mid morning to mid evening hours or do not have access to air conditioning. See extended discussion below for weather details.
A large south swell from Major Hurricane Genevieve will further enhance large wave and potentially deadly rip currents for some area beaches. See Beaches discussion below and associated coastal hazard products for details.
In the meantime, pretty dull (but warm) weather on tap for the short term. The upper level pattern will not change much over the next 72 hours with a powerful 597 dam upper high centered over the TX and OK panhandles. At the sfc there will be mdt-stg (strongest in the late afternoon) onshore flow to the east. The N/S gradient will vary from weak offshore in the morning to weak onshore in the afternoon.
The morning low cloud pattern will not change much at all. The low clouds will be likely across the LA csts and the western SBA cst. There will also be a 30-40 percent chc of low clouds reaching the VTA csts as well as the SLO cst.
There will be another round of gusty Sundowner winds across southwest Santa Barbara County the winds look a little weaker than last evenings and will likely come in just under advisory levels.
Today will be the last day of the current heat advisory as the combination of 95 to 101 degree temperatures and higher than normal humidity will continue the hazardous heat levels. There will be a a degree or two of cooling for most areas Tuesday and Wednesday as hgts fall a little. More importantly drier air will sweep in from the NW (PWATs fall from around 1 inch to near 0.70) and this will make the lower temps feel even better. That said the higher than normal sea sfc temps will keep humidities a little above normal especially near the coast.
On Thursday the upper high begins to migrate back to the west, initiating widespread warming with a moderate 60 percent chance of reaching advisory levels for interior areas by Thursday. More widespread and significant warming will continue into the weekend.
(Fri-Mon), 27/143 PM.
Widespread MODERATE TO HIGH heat risk is very likely to return Friday into the weekend. Now is the time to start socializing this threat with your community and family and consider rescheduling activities that might but you or your loved ones at risk. Have a plan to stay cool, especially if work or other activities take you outside mid-morning to mid-evening hours or do not have access to air conditioning.
RECORD BREAKING or tying (for at least July since 1999) 500 mb heights of 598-600 dm is likely sometime Friday into Saturday with only modest weakening into early next week. A Heat Watch will eventually be needed to cover this very concerning period (especially Friday through Sunday) Widespread highs of 95-105 away from the coast with pockets of 105-115 in warmest coastal valleys to interior are likely during the peak of the heatwave Friday and Saturday. Highs 80-95 will be common coastal areas away from the beaches. Overnight lows in the 70s and 80s for many areas will increase risk for heat stress through prolonged exposure and limited ability for dwellings without air conditioning to cool overnight.
There is also an increased risk for large and dangerous fires due to the hot and unstable conditions with pockets of gusty winds, perhaps, especially southwest Santa Barbara County and the I-5 corridor in the mountains into the weekend.
Night to morning low clouds will diminish or disappear during this time, although weakened onshore focused to the east will somewhat limit the heat nearest the coast. However, well above normal water temperatures will somewhat maintain the humid muggy feeling near the coast, decreasing the body's ability to cool through sweating.
27/1726z.
At 1630Z at KLAX, the marine layer was 1400 ft deep. The top of the inversion was near 4700 ft with a temperature of 24 Celsius.
High confidence in TAFs for KBUR KVNY KPMD KWJF and KPRB.
Moderate confidence in TAFs for KLGB, KLAX KSBP and KSMX where the arrival and departure times of CIGs could be off by +/- 2 hours. Min CIG heights may be off by +/- 200 feet, with a 20% chance for VLIFR conds at KSMX/KSBP.
Fair confidence in TAFs for KSBA and KCMA with only a 15 percent chc of IFR cigs 13Z-17Z.
Moderate confidence in TAFs for KOXR and KSMO with a 30 percent chc of IFR/LIFR cig/vis 12Z-17Z.
KLAX, Moderate confidence in TAF. Cigs could arrive as early as 07Z and as late as 12Z with transition to VFR sometimes 28/15Z-18Z. High confidence in any east winds staying under 8 knots.
KBUR, High confidence in CAVU TAF.
27/202 PM.
Good confidence in a prolonged period of gusty northwest winds across the coastal waters through this week, except for nearshore south of Point Concpetion (including eastern Santa Barbara Channel and the waters adjacent to the Los Angeles and Orange County coasts). Small Craft Advisory (SCA) conditions will fairly persistent, with periods of marginal Gale Force Winds near 35 knots this afternoon and evening, and potentially again tomorrow afternoon and evening.
Nearshore south of Point Conception, marginal SCA level winds (20-25 knots) will become common across the western half of the Santa Barbara Channel each afternoon and evening with low chances of extending into eastern portions of the Channel. However, today is an exception where marginal SCA level winds are forecast across the eastern half of the Channel through this evening. The southern nearshore waters are expected to see winds remain below 20 knots.
Seas are expected to hover near 8-10 feet across the waters away from the coasts much of the week. A southerly swell from Hurricane Genevieve will send a modest southerly swell into the waters tonight into tomorrow, which will continue into the weekend. This south swell may impact south facing harbors, including Port San Luis.
27/202 PM.
An extended period of a combination of moderate to long period southerly swells will continue through this week and into next weekend. A long 17-20 second period SSW Southern Hemisphere swell will continue to impact our area through mid week. Then Category 5 Hurricane Genevieve will send another southerly swell to SoCal Tuesday.
A Beach Hazards Statement is in effect through Wednesday (except through Saturday along the Central Coast) due to the increased risk of dangerous rip currents and elevated surf. There have been numerous ocean rescues reported.
A High Surf Advisory has been issued for Wednesday evening through Saturday evening for the incoming southerly swell due to Hurricane Genevieve, particularly for south facing beaches exposed to southerly swell (such as from Manhattan Beach to Port Hueneme along the Malibu Coast, and from Long Beach to the Palos Verdes Peninsula). This swell will peak around 3-5 feet at 12-15 seconds from 160-180 degrees.
Additionally, a Coastal Flood Advisory has been issued for Wednesday evening through Friday evening for the Ventura and Los Angeles County Coasts. High tides of 6.2-7.0 feet will peak in the evening hours. In conjunction with the highest expected surf from the Hurricane Genevieve southerly swell, the best potential for minor coastal flooding impacts is expected Wednesday and Thursday evening. Generally minor impacts are expected, such as pooling of seawater over low lying coastal areas in susceptible areas.
Ca, Heat Advisory remains in effect until 8 PM PDT this evening for zones 38-88-342>345-348>358-362-366>382-548. (See LAXNPWLOX). Beach Hazards Statement in effect through Saturday afternoon for zones 340-346. (See LAXCFWLOX). Beach Hazards Statement in effect through Wednesday afternoon for zones 354-362-366. (See LAXCFWLOX). Coastal Flood Advisory in effect from 5 PM Wednesday to 3 AM PDT Saturday for zones 354-362-366. (See LAXCFWLOX). High Surf Advisory in effect from 5 PM Wednesday to 5 PM PDT Saturday for zones 354-362-366. (See LAXCFWLOX). Extreme Heat Warning in effect until 8 PM PDT this evening for zone 383. (See LAXNPWLOX). PZ, Small Craft Advisory in effect until 3 AM PDT Tuesday for zone 645. (See LAXMWWLOX). Small Craft Advisory in effect until 9 PM PDT this evening for zone 650. (See LAXMWWLOX). Small Craft Advisory in effect until 3 PM PDT this afternoon for zones 670-673-676. (See LAXMWWLOX). Gale Warning in effect until 3 AM PDT Tuesday for zones 670-673-676. (See LAXMWWLOX).
