So Cal Weather


#1

Looks like we are in for another round of heat, from NWS LA.

From Weather West:


NWS LA - Red Flag for Santa Barbara County
SoCal weather
#2

Fire Weather watch for SBC:

FIRE WEATHER MESSAGE 935 AM PDT Sun 7/22/2018 …FIRE WEATHER WATCH IN EFFECT LATE TUESDAY AFTERNOON THROUGH THURSDAY MORNING FOR SANTA BARBARA COUNTY MOUNTAINS AND SOUTH COAST DUE TO GUSTY NORTHWEST TO NORTH WINDS, LOW HUMIDITIES, AND HOT TEMPS. (per NWS)


#3

Santa Barbara County South Coast-Santa Barbara County Mountains-
111 PM Mon Jul 23

…RED FLAG WARNING REMAINS IN EFFECT FROM 3 PM TUESDAY TO 10 AM
PDT THURSDAY FOR GUSTY NORTH WINDS WITH HOT AND DRY CONDITIONS…

  • Winds…Areas of northwest to north winds 20 to 40 mph with
    ** gusts to 55 mph.** Winds will be strongest around the Santa Ynez
    Range, from the San Marcos Pass and westward, during the late
    afternoon and overnight hours.

  • Relative Humidity…Minimum humidities between 10 and 20
    ** percent** in foothills and wind prone areas, with poor overnight
    recovery.

  • Temperatures…Maximum temperatures between 95 and 105 degrees
    inland of the beaches, with warm overnight conditions.

New weather stations in the sundowner area added to cam page: http://www.rntl.net/santabarbaracountyfirecams.htm


#4

Anyone have update on weather for upcoming week or two for possible Santa Ana’s?


CNR Weather
#5

Found these in regards to Santa Ana’s… their twitter says the 27th being the first event but had no other details

https://mobile.twitter.com/sawti_forecast?ref_src=twsrc^tfw|twcamp^embeddedtimeline|twterm^profile%3Asawti_forecast&ref_url=https%3A%2F%2Ffsapps.nwcg.gov%2Fpsp%2Fsawti

https://fsapps.nwcg.gov/psp/sawti


#6

Thank you for the info


#7

Good afternoon. I have not posted in a while, so I thought it would be a good time for a weather update :).

Through the upcoming weekend, there is nothing too exciting in the offing for SoCal weather. An upper level ridge will gradually build over the area while surface pressure gradients remain weak. So, coastal stratus/fog will be limited while temperatures generally will climb a couple degrees above normal. Away from the coast, relative humidity will remain rather low with poor overnight recovery. As for winds, there will be some north to northeast winds across the area tonight/Thursday morning (but below advisory levels) then weak onshore flow through the weekend. So, there will be elevated fire weather conditions across interior sections of SoCal.

For the first half of next week, relatively persistent conditions will continue with warm temperatures, low RH away from the coast and weak to moderate onshore winds. For the second half of next week, the upper level ridge will strengthen once again over the area, bringing warmer and drier conditions. Earlier model runs hinted at the possibility of a weak Santa Ana wind event around next Thursday or Friday. However, the model runs today have backed off that possibility. So, do not anticipate any type of significant offshore wind event, just relatively weak diurnal flow (onshore during the day and offshore at night) with rather warm and dry conditions.

Further out, it looks like a decent chance of continued above normal temperatures and dry conditions into early October.


#8

Good afternoon. Just wanted to post a quick weather update for the rather interesting situation next week.

In the short term, an upper-level low pressure system will develop over the Eastern Pacific and move northeastward this weekend across NorCal. For SoCal, this pattern will result in cooler temperatures and a bit of an increase in relative humidity. Additionally, onshore gradients will strengthen, resulting in gusty afternoon and evening winds across interior sections.

For the 1st half of next week, things are quite interesting. The remnants from Hurricane Rosa are expected to move across Baja Mexico and into Arizona. Additionally, another upper-level low pressure system is forecast to either move across SoCal early next week or linger just off our coast. So, there definitely is a decent chance of some rainfall for SoCal from Monday night through Wednesday. At this time, the effects of Rosa, in terms of precipitation, will be mainly impacting SE California as well as Arizona and into the Great Basin where some heavy rainfall will be likely. With regard to the upper-level low pressure system, it will bring some decent moisture with it as well as tapping into a bit of the Rosa moisture. So, there should be some measurable precip across most of SoCal from Monday night through Wednesday. Amounts are still tricky at this time, but there is the potential for some decent rainfall across the area.

So, get those umbrellas handy next week…and stay safe.

Wx_Guy


#9

Thanks WX!
Between you, the GACC, weatherbug… I don’t know how people can stand to sit and listen to tv weather. There are people, such as yourself, who know way more!!!


#10

weather bug app? 12 days out GFS shows another tropical storm/trough set up for So Cal…yeah I know anything passed 5 days is weather fantasy land…


#11

Good afternoon. Just a quick forecast update for your Monday.

In the short term, SoCal will have rather unremarkable weather as an upper-level trough settles over the Great Basin. With this pattern, there should be an increase in coastal stratus/fog as well as a cooling trend for all areas. Winds will exhibit the typical diurnal trends.

For Friday through the weekend (and into early next week), things are really muddled as the computer models are all over the place (leading to a low confidence forecast) due to having to handle the remnants of Hurricane Sergio. One model (GFS) develops a cutoff low off the SoCal coast this weekend which results in the potential for some precipitation across the area and weak onshore flow across the area. The other models (ECMWF) is more progressive with a cutoff low taking it into AZ/NM. The ECMWF solution would keep SoCal dry this weekend and generate offshore flow (with the potential for a decent Santa Ana by Sunday).

For early next week, the GFS begins to “catch up” with the ECMWF solution, indicating an extended period of offshore flow.

As stated earlier, forecast confidence is rather low at this time. However, just keep in your mind that there could be an extended period of warm and dry offshore flow this weekend and early next week or even a chance of some precipitation over SoCal.

Stay tuned to the latest forecasts from the NWS and GACC as this situation could be rather dynamic with respect to day-to-day forecast changes.

Be safe out there.

Wx_Guy


#12

Wx-Guy, thanks for keeping us updated. I appreciate you coming to this website to continue to share your perspective, especially this time of year when our eyes are so focused on the forecast and the fine line between rain and wind.


#13

NWS Los Angeles - 10am - Looks like the first decent offshore event of the season will arrive Monday which is a pretty late date. Mdls struggling with the exact amount of offshore flow but it looks like there will be advisory level gusts at least. Skies will be clear and there will be a good warm up to the lee of the mtns.

Grad reverse on Tuesday and its likely that a weak marine layer stratus deck will develop. Max temps will cool (esp along the coast) due to the switch from offshore to onshore flow.


#14

Good morning. Just a quick SoCal forecast update as the models have come into better agreement.

Overall, it still looks like an interesting few days of weather for SoCal. Main feature in the short-term will be a cutoff low (the bane of my existence). By late Thursday, a cutoff low forms off the Central Coast and slowly meanders south and east, moving across far Southern CA Saturday afternoon/evening. By late Friday night and Saturday, this system will bring up some moisture into the area, bringing the threat of rain through Saturday evening. At this time, the best chances of rain look to be across San Diego county with the chances gradually diminishing up to Ventura county. Confidence in rainfall amounts is moderate at best with San Diego county forecast to receive between 0.75 and 1.50 inches (highest totals in the mountains) to a trace to 0.50 inches across Los Angeles and Ventura counties (with highest totals likely across the San Gabriel Mtns). As we draw closer to the time period of rainfall, the forecast amounts will likely change, so stay alert to the latest forecasts.

After the threat of rain moves through, attention turns to an extended period of offshore flow. By Monday morning, surface high pressure builds into the Great Basin, setting the stage for a several day Santa Ana wind event (Monday through Wednesday). Models indicate offshore gradients (LAX-DAG) bottoming out around -5.5 mb Monday morning with gradually weakening offshore gradients Tuesday and Wednesday. Upper level wind support looks decent Monday and Tuesday. So at this time, I would expect advisory-level northeast winds Monday and Tuesday (with gusts up to 50 MPH in the windier spots, especially Monday morning) with weaker winds on Wednesday.

As one would expect, as the Santa Ana winds build, warmer and drier conditions will develop. Temperatures will be noticeably above normal while relative humidity drops into the teens and single digits (with poor overnight recoveries). Weather-wise, critical fire weather conditions are a definite possibility Monday and Tuesday (and to a lesser extent on Wednesday). Obviously, the amount of rain that some areas could receive on Saturday will temper the impact of critical fire weather conditions early next week. However, it will not take long for these conditions to dry things out.

The details of the forecast for the next few days could change. However, there is the potential for some wetting rain as well as an extended period of offshore flow. So stay tuned to the latest forecast information from the NWS and GACC.

Stay safe out there!!!

Wx_Guy


#15

@sawti_forecast
The 1st Santa Ana wind event of the season will arrive late Sunday night/early Monday morning and will last through late Tuesday. Greatest fire threat will be over LA/Ventura Counties. Stay tuned.

The fire potential with this Santa Ana event is Marginal. Local northeast winds of 15-30 mph, along with higher gusts can be expected. Humidity values will drop to 8-15%. Recent rains have moderated fuel conditions slightly, but not enough to prevent significant fires from occurring in the more wind prone areas.


#16

From @weather_west

Interesting weather set-up in SoCal next 36 hrs. Offshore cut-off low will destabilize atmosphere & induce easterly flow, bringing both widespread chance of thunderstorms (including coast) & Santa Ana winds. Rare instance of Santa Ana-driven lightning fires possible.#CAwx #CAfire


#17

Fire Weather Watch just issued…

…FIRE WEATHER WATCH IN EFFECT FROM SUNDAY NIGHT THROUGH TUESDAY
EVENING FOR GUSTY OFFSHORE WINDS AND LOW RELATIVE HUMIDITY OVER
MOST OF LOS ANGELES AND VENTURA COUNTIES…

.Gusty northeast winds will return Sunday afternoon and continue
through Wednesday, with strong upper level support. These winds
will peak Sunday night through Monday when gusts in the 35 to 55
mph range are expected over the favored areas of Los Angeles and
Ventura Counties. Widespread minimum humidities between 5 and 10
percent are likely. As a result, critical fire weather conditions
are possible by Sunday night continuing through Tuesday over most
of Los Angeles and Ventura Counties. There is a chance that
critical condition persist through Wednesday. This Fire Weather
Watch will likely be converted to a Red Flag Warning over the
weekend.


#18

Projected wind speed and gusts from the Euro Model:


#19

Fire Weather Watch just now issued for San Diego and surrounding areas also…

Fire Weather Watch
URGENT - FIRE WEATHER MESSAGE
National Weather Service San Diego CA
107 PM PDT Fri Oct 12 2018

…STRONG AND DRY OFFSHORE WINDS SUNDAY NIGHT THROUGH TUESDAY…

CAZ248-250-255>258-552-554-131100-
/O.NEW.KSGX.FW.A.0003.181015T1000Z-181017T0300Z/
San Bernardino and Riverside County Valleys - The Inland Empire-
San Diego County Inland Valleys-San Bernardino County Mountains-
Including The Mountain Top And Front Country Ranger Districts Of
The San Bernardino National Forest-Riverside County Mountains-
Including The San Jacinto Ranger District Of The San Bernardino
National Forest-Santa Ana Mountains-
Including The Trabuco Ranger District of the Cleveland National
Forest-San Diego County Mountains-
Including The Palomar And Descanso Ranger Districts of the
Cleveland National Forest-Orange County Coastal Areas-
Orange County Inland Areas-
107 PM PDT Fri Oct 12 2018

…FIRE WEATHER WATCH IN EFFECT FROM LATE SATURDAY NIGHT THROUGH
TUESDAY EVENING FOR STRONG GUSTY WINDS AND LOW HUMIDITY FOR
MOUNTAINS, VALLEYS AND ORANGE COUNTY…

The National Weather Service in San Diego has issued a a Fire
Weather Watch…which is in effect from late Saturday night
through Tuesday evening.

  • LOCATION…Mountains, particularly the foothills below 6,000
    feet elevation, valleys and Orange County.

  • WIND…Northeast 25 to 35 mph with gusts to 50 mph. Isolated
    gusts to 60 mph in foothills.

  • HUMIDITY…Dropping rapidly Monday to 5 to 15 percent away from
    the coast. Poor recovery Monday night.

  • TIMING…Sunday night through Tuesday. Strongest winds Monday
    morning and lowest humidity Monday afternoon.

  • OUTLOOK…Gradually decreasing winds late Tuesday and
    Wednesday.

  • IMPACTS…Any fires that develop will likely spread rapidly.
    Outdoor burning is not recommended.


#20

Another quick weather update for your Saturday.

Well, it was a pretty good light show for SoCal last evening and this morning. Between the showers and thunderstorms, most areas in SoCal received between 0.25 and 1.00 inches of rainfall. The showers will end from northwest to southeast through the day today. Obviously, the rainfall was very welcome. However with the chance to dry out today and Sunday, I would think the mitigating effects of the rainfall upon the upcoming Santa Ana wind event would be minimized.

With respect to the upcoming Santa Ana wind event, everything I have seen the last couple of night shifts still point to a significant event. All models are in remarkable synoptic (large scale) agreement with the pattern albeit with their inherent differences (ie NAM is stronger with forecast parameters than GFS due to differences in resolution and model type). That being said, all models indicate a great combination of ingredients for a significant wind event: strong offshore pressure gradients and impressive upper level wind and thermal support). Moderate to strong Santa Ana winds will develop Sunday night and Monday (gusts 40-60 MPH likely) with somewhat weaker winds Monday night and Tuesday. As the winds develop, temperatures will be on the rise and relative humidity will be dropping (widespread single digit readings Monday and Tuesday with poor overnight recovery). Widespread and long duration critical fire weather conditions are likely and current FIRE WEATHER WATCHES will likely be upgraded to RED FLAG WARNINGS either today or Sunday.

From Wednesday through the end of the week, offshore flow will continue across SoCal, but will gradually weaken from day-to-day. Temperatures will remain above normal with low relative humidity. So, elevated fire weather conditions can be expected Wednesday into the weekend.

Given the current critical Live Fuel Moisture and the anticipated weather conditions, the next few days could be very interesting. Again, the recent rainfall is helpful, but should not be counted on to significantly mitigate this upcoming Santa Ana event.

Stay safe out there!!!

Wx_Guy