November 19, 2019
Summary: Central California is under attack by two low pressure systems. The first is a low pressure system off the coast of northern Baja which is spreading showers as far north as the Mexico border. Second is a rather dry system which is now centered in southern Oregon and is digging rapidly southward into northern California. A dry cold front is moving through with a fairly wide band of high clouds, but the cold upper portion of the low is still mainly in Oregon.
By this evening, the low will be just northwest of San Francisco then just off the central coast by roughly midnight or so. Showers of rain and snow will spread down the Sierra Nevada beginning late this afternoon with an increasing chance of scattered light showers over the valley floor tonight and Wednesday.
As mentioned in earlier reports, the valley will be in a reverse rain shadow. Typically during winter storms, we see a rain shadow along the west side of the valley next to the Coast Range. This time around, the counterclockwise circulation of the low will have winds aloft out of the east to northeast, creating a rain shadow along the west facing slopes of the Sierra Nevada. Precipitation amounts will be pretty significant over the high Sierra and possibly the Kern County mountains, but on the valley floor, amounts will be generally less than .10 with possibly only trace amounts in some locations.
The best chance of rain will be along the far eastern side, mainly in Tulare County but more so in Kern County.
Models are indicating this system has really sped up. The center of circulation will have already dove into extreme southern California by midday Wednesday with only a chance of showers Wednesday afternoon. Dry weather will return Wednesday night and will last for at least the remainder of the week. Even though a weak low center is projected to form just off the central coast, all of the models indicate this system will be dry. It will keep pressure patterns pretty low over central California so no significant warm up is expected over the weekend with readings generally in the mid to upper 60s.
From Monday through Wednesday of next week, another interesting pattern should evolve. A cold low will drop southward from western Canada into the Great Basin, possibly just east of the Sierra Nevada. Some models indicate the jet stream will be running northeast to southwest right into California which would give a chance of rain and snow showers over the Sierra Nevada but just dry weather on the valley floor. A colder air mass would invade from the north, possibly leading to some frost nights beginning Tuesday morning, although that remains to be seen. It depends on how the various players fall into place.
Longer range models are suggesting some potentially active weather between the 28 and 30 of this month. Some models, though, point to the storm track remaining too far to the north. We’ll see.
Forecast: Increasing cloudiness today. Mostly cloudy tonight and Wednesday with scattered light showers later tonight and Wednesday morning. A chance of light showers Wednesday afternoon, mainly in Kern County. Partly to mostly cloudy Wednesday night and Thursday morning. Mostly clear to occasionally partly cloudy Thursday afternoon through Sunday night. increasing cloudiness Monday. Variable cloudiness Monday night and Tuesday.
Short Term:
| Madera 71/42/57/38/62 | Reedley 72/41/58/39/63 | Dinuba 71/42/58/38/61 |
| Porterville 74/41/58/39/63 | Lindsay 74/42/57/37/63 | Delano 74/43/58/41/64 |
| Bakersfield 75/49/57/44/62 | Taft 75/50/58/47/63 | Arvin 76/46/57/43/64 |
| Lamont 75/44/59/42/64 | Pixley 75/43/58/39/62 | Tulare 73/43/58/37/62 |
| Woodlake 73/43/58/38/63 | Hanford 73/44/58/39/62 | Orosi 73/42/57/37/63 |
Seven Day Forecast:
| Friday
Partly cloudy 40/65 |
Saturday
Mostly clear 39/66 |
Sunday
Mostly clear 38/67 |
Monday
Increasing clouds 38/63 |
Tuesday
Variable clouds 33/58 |
Two Week Outlook: November 26 through December 2: This model is indicating the possibility of an active pattern between the 28 and the 1st for a chance of rain. This model is also indicating below average temperatures over much of the lower 48, this time including California.
November: The greatest possibility of above average temperatures will stretch from Texas westward to southern California with somewhat above average temperatures expected for central California. This model also projects a drier than average month, especially over the northern half of the state.
December, January, February: This model, as it always does, indicates above average temperatures for much of the lower 48, especially over the southwestern U.S. This model also dashes somewhat the hope for a good rainfall season as it shows below average precipitation for the Pacific Northwest and much of California.
Winds: Winds later today will be out of the west then the northwest this evening at 10 to 15 MPH with local gusts to 25 MPH. winds Wednesday will be mainly out of the northwest at 8 to 15 MPH, diminishing Wednesday night. Winds Thursday and Friday will be generally at or less than 6 MPH with periods of near calm conditions.
Rain: Showers and thunderstorms are spreading into far southern California at this hour from an upper low off the northern Baja, California coast which will move northeastward into southeast California and Arizona tonight and Wednesday with numerous showers and thunderstorms there. In the meantime, to our north a low center is digging a trough into northern California and will be just to the west of San Francisco later tonight. It will be near Santa Barbara by early Wednesday morning. Numerous showers will spread down the Sierra Nevada beginning late this afternoon with light showers over the valley floor. We’re in one of these rare times where a reverse rain shadow will occur along the Sierra Nevada, certainly reducing the chance of any significant precipitation on the valley floor. Some locations towards the center of the valley may just pick up trace amounts. The best chance for measurable rain will be in far eastern Tulare County and over much of the valley region of Kern County tonight through Wednesday.
Rainfall amounts will range from trace amounts to .10 over most of the valley. It’s possible isolated locations, mainly over the valley portion of Kern County, could pick up .25 or so. Dry weather will return by Wednesday evening and will continue through Monday.
Another low will dive into the interior west late Monday through Wednesday for a chance of showers over the Sierra Nevada. For now, we’ll keep the valley forecast dry, but we’ll certainly be watching.
Some of the longer range models are showing an active pattern trying to develop over northern California from the 28 through the 30. We’ll see if any trends develop on that, as well.
Frost Discussion: All locations will be above freezing through Monday morning. I’m closely watching various trends on models for Monday through Wednesday of next week. There is the possibility of a rather vigorous low dropping into the interior west just to the east of the Sierra Nevada while a ridge of high pressure builds northeastward into the Gulf of Alaska, possibly as far north as northwest Canada. This creates a north/northeast flow wrapping around the back side of that system over the interior west and also generates a strong off shore flow. This combination could, in theory, drop temperatures into the upper 20s to lower 30s beginning Tuesday of next week. This, of course, is tentative at this time, but certainly something to be aware of.
Lows Tonight:
All locations will be above 32 tonight.
___________________________________________________________________________________________
Afternoon Dew Points Today: Upper 40s to the lower 50s. Kern: Mid to upper 40s. Humidity values ranging from 45%/95% at Hanford. Bakersfield 30%/95%
Actual Humidity range November 18, 2019: Delano, 91%/3% Porterville, 96%/29%
Percentage of Sunshine Today/Tomorrow: Visalia: Today: 30%, tomorrow 20%. Bakersfield: Today: 50% Tomorrow: 10%
ET Rates Over the Past Seven Days: Stratford .60, Parlier .56, Blackwell Corner .59, Arvin .66, Orange Cove .59, Porterville .57, Delano .57. Courtesy University of California *=estimate, NA=not available.
Seven Day Soil Temperatures: Stratford 60, Parlier 59, Blackwell 65, Arvin, 59, Orange Cove 61, Porterville 63, Delano 57
Record Temperatures: 83/29. Average Temperatures: 63/39
Heating Degree Days this Season: 209 -92
Courtesy of the NWS
Average temperature for November so far: 59.2- +5.0
Precipitation: Seasonal total/average/above or below average:
Since Oct 1, 2018 Fresno: 0.00 season. or -1.25 Month to Date: .00 -.62
Since Oct 1, 2018, Bakersfield: 0.00, or -.66. Month to Date: .00 -.36
Water year season is from October 1st through September.
Chilling Hours November 1st through February 28: Orange Cove 63, Parlier 111, Arvin 53, Shafter 81, Stratford 76, Delano 89, Lindcove 71, Porterville 147,
Hours at 45 or below 45.
Sunrise: 6:42 Sunset: 4:47 pm. Hours of Daylight: 10:06
Yesterday’s Weather:
MAE : Madera 253 : DH1600 / 75 / 42 / 0.00 /
FAT : Fresno Airport 333 : DH1600 / 77 / 48 / 0.00 /
HJO : Hanford Airport 242 : DH1600 / 79 / 43 / 0.00 /
NLC : Lemoore Naval AS 234 : DH1600 / 77 / 38 / 0.00 /
BFL : Bakersfield Airport 496 : DH1600 / 76 / 49 / 0.00 /
VIS : Visalia Airport 292 : DH1600 / 77 / 42 / 0.00 /
ATEC1 : Avenal 787 : DH1544 / 77 / 45 / M /
PTV : Porterville Airport 442 : DH1600 / 80 / 42 / 0.00 /
TFTC1 : Taft 759 : DH1549 / 78 / 53 / 0.00 /
LOSC1 : Los Banos 120 : DH1600 / M / 45 / 0.00 /
Rainfall: Water year Oct 1st through September 30th
24hr season % last year % Ave. 365 day ave.
STOCKTON 0.00 0.00 0 1.28 72 1.79 14.06
MODESTO 0.00 0.00 0 0.01 1 1.43 13.11
MERCED 0.00 0.00 0 T 0 1.56 12.50
MADERA 0.00 0.00 0 T 0 1.61 12.02
FRESNO 0.00 0.00 0 0.10 8 1.25 11.50
HANFORD 0.00 0.00 0 0.04 3 1.21 10.10
BAKERSFIELD 0.00 0.00 0 0.00 0 0.66 6.47
BISHOP 0.00 0.00 0 0.40 67 0.60 5.18
SALINAS 0.00 0.00 0 0.67 51 1.32 12.83
PASO ROBLES 0.00 0.00 0 0.03 2 1.22 12.78
SANTA MARIA 0.00 0.00 0 0.35 26 1.34 13.95
Next report: Tuesday, November 19/pm