16 Day Forecast, Tuesday, December 31th, thru Thursday evening, January, 16th, 2014;
HAPPY NEW YEAR! Lots of info to digest in this special edition, End of the Year 2013 Forecast.
HISTORIC 2013 DROUGHT SHATTERS PREVIOUS RECORDS! (Important Details below↓) .
The outlook for precip is becoming a major concern as official news of the severity of the 2013 Drought is published. The16 Day Outlook from the GFS ending Thursday, January 16th shows most of CA bone DRY! The numbers crunched today highlight the seriousness of the developing Drought situation, which is in new record territory for the State of CA.
Wx Headline; Critical Temps are likely Wednesday morning at the coldest Stations, with freezing temps at the coldest Ag Stations for the next week.
…and the seemingly endless broken record continues with dry air producing clear skies with a wide range of diurnal temps. Sunny skies and record-setting warm afternoon temps followed by clear skies overnight producing rapid radiational cooling for cold frosty minimum temps in the morning. The trend for wide diurnal temp spreads continues this week with minor fluctuations occurring each day. Many Eastside Citrus Belt Stations are experiencing nightly episodes of downsloping drainage winds overnight which modifies temps by a few degrees thru adiabatic heating and this is likely to continue. Regions along the Westside, Lake Bottoms and wind sheltered spots of the Eastside continue to experience strong radiational cooling with 22 SJV stations reporting Critical temps 28° or below last night, with the coldest temp in the SJV Ag Districts dipping to 25°! The easterly downsloping winds each night are continuing to advect extremely dry air into CENCAL, thereby compounding the extreme variance in the diurnal temp range.
HISTORIC RECORD-SETTING DRYNESS occurred Tuesday, New Years Eve at most official Stations throughout the entire State of CA for the Annual Calendar Year, Jan-Dec 2013 Precip Total (Not the Water Year Oct-Sep). Many NWS WFO’s are still sifting thru their Record Books, so the list below is still incomplete, but many of the precip totals listed are extraordinary and supersede the greatest drought years in CA history by leaps! For example, San Francisco (the oldest wx record in CA) shattered its previous record 1917, 96 years ago by a whopping shortage of -3.41 inches, a 38% decrease from the previous record! In addition one of the most stunning new records is at one of the most important Stations in CA, Shasta Dam, which shattered its previous dry year by a whopping -11.10 inches! The list below ↓illustrates how many Stations smashed their old records from the Great 1976 Drought Year! All the Stations listed below recorded new record dryness for the 12 month period. The future Water Outlook is appearing more bleak by the day as the GFS forecast model remains steadfastly DRY thru Jan 15th. Here is a preliminary glance at a few of the NEW RECORD-SETTING LOW PRECIP totals for 2013 (more to come);
Station 2013 New Record Previous Record__ Average
NO Sierra 8-Stn Index 16.48 18.90 set in 1976 50.00 Important Water Supply Index record beat by -2.42 inches, 13% decrease
SO Sierra 5-Stn Index 10.48 17.92 set in 1908 40.80 Important Water Supply Index record shattered by -7.44 inches, 41% decrease
Fresno 3.01 3.55 set in 1947 11.50
Hanford 2.24 3.37 set in 1947 8.96
Lindsay 2.91 4.03 set in 1947 12.46
Los Banos 2.28 2.98 set in 1953 9.95
Modesto 4.45 5.70 set in 1929 12.14
Merced 3.79 6.00 set in 2007 12.50
Visalia 3.47 4.10 set in 1910 10.93
Lodgepole 11.73 18.54 set in 1953 45.48
S Entrance YNP 10.84 13.65 set in 1976 41.25
YNP 11.24 14.84 set in 1976 35.95
Crescent City 28.92 33.21 set in 1976 64.03
Eureka 16.40 21.17 set in 1976 40.33
Ukiah 7.50 (Wow) 14.10 set in 1976 37.35
Shasta Dam 16.89 27.99 set in 1976 62.72 Shattering the previous record by -11.10 inches, a decrease of 40%
San Francisco 5.59 (Wow) 9.00 set in 1917 23.65 Shattering the previous 96 year old record by a huge 62%!
SFO 3.38 9.22 set in 1953 20.65
Gilroy 2.56 11.88 set in 2007, 1977 20.54
Los Gatos 3.24 9.47 set in 2007 23.08
Newark 3.36 6.90 set in 1976 15.09
Redwood City 3.36 8.03 set in 1976 20.32
San Jose 3.80 6.04 set in 1929 14.90
Oakland Dwntwn 4.24 10.02 set in 1976 23.96 Shatters the previous record by a decrease of -5.28 inches, 58%!
OAK 4.89 8.65 set in 1976 20.81
San Rafael 5.59 13.41 set in 1990 35.23 Shatters the previous record by -7.82 inches, a decrease by 58%
Petaluma 5.62 8.99 set in 1976 26.65
Calistoga 6.13 12.43 set in 1976 40.87
Richmond 6.47 8.98 set in 1976 24.93
Mt Diablo 6.56 8.91 set in 1976 25.04
Ben Lomond 6.57 20.45 set in 1976 50.48 Obliterates the prior record by -13.88 inches…a whopping 68%!
Livermore 4.50 6.41 set in 1976 15.23
Saint Helena 4.72 10.42 set in 1976 36.64
Napa 6.74 10.39 set in 1939 27.71
Berkeley 6.76 9.92 set in 1929 26.74
Cloverdale 7.77 14.52 set in 1976 43.13
Kentfield 7.80 20.30 set in 1939 47.98 Shatters the prior record by -12.50 inches, a decrease by a huge 62%!
Muir Woods 12.69 16.82 set in 1976 38.26
Occidental 15.45 20.76 set in 1976 56.99
King City 1.98 3.14 set in 1953 12.06
Pinnacles 2.70 6.08 set in 1947 17.24
Watsonville 3.18 10.66 set in 1976 23.50
Salinas Apt 3.27 5.76 set in 1953 12.83
Salinas 3.94 7.33 set in 1961 15.45
Monterey 4.19 8.96 set in 1953 21.10
Santa Cruz 5.07 11.86 set in 1929 31.35
Tahoe City 8.08 9.34 set in 1976 31.55
Sacramento 6.12 6.67 set in 1976 n/a
LA Dwntwn 3.60 4.08 set in 1953 “
Burbank 3.03 3.55 set in 1947 “
Camarillo 2.97 3.44 set in 2007 “
Santa Maria 2.99 3.30 set in 1989 “
Paso Robles 1.92 4.20 set in 2007 “
Special Notation; THE BOTTOM LINE…The 2013 Drought numbers tallied on Tuesday and are set forth as illustrated above and that list is incomplete by the way. The new record dry precip totals are stunning from a climate stand point. We knew that they were going to be dry, but didn’t expect the magnitude of the dryness, especially spread over such a vast area. Reviewing them in detail is mindboggling to meteorologists and climatologists, and putting this bluntly…the Drought of 2013 appears to be in a new category all by itself according to how the new records fit into past climate records. The previous historic dry records have been completely demolished, being shattered by very large deficit numbers which are staggering with complications for the future health and well being of the CA economy and CA AG! With the GFS 16Day QPF Outlook not cooperating with the hint of rainfall…the news thus far this season for water is dismal at best. It would require biblical epic-type rainfall across CA to mitigate the damage that is setting up in the river water basins and the snowpack. At this point, unless the GFS radically changes its tune, thusly creating a Miracle February and a Miracle March, the CA water supply is heading for severe restrictions. The past month of December 2013 had record-setting cold, record-setting heat, record-setting dryness for the month and also ended 2013 with a truly historic unprecedented Drought! This also comes at a time in which the CPC is forecasting a hotter than average summer for CA.
December Regional City Precip Summary
CALIFORNIA SNOW WATER CONTENT; Percent of April 1 Average, December 30, 2013 (Note the short pink lines representing the current season)
Fresno had the 5th driest start to the Rainfall Year on record for the 6 month period July to December
1) 1917 0.49
2) 1929 0.51
3) 1999 0.52
4) 1980 0.67
5) 2013 0.73
San Francisco had the 4th driest start to the Rainfall Year on record for the 6 month period July to December
1) 1917 1.55
2) 1958 1.78
3) 1956 1.89
4) 2013 2.08
Observations this morning show the nearest precip to CA is into western MT. Satellite Imagery this morning shows a rapidly decaying cold front fizzling out over CENCAL with diminishing cloudiness. A pocket of dry air remains in the Kern River basin with dewpoints dipping into the single digits, meanwhile dewpoints are recovering slowly over the rest of CENCAL.
24hr Precip Summary highlights; none
Current Synoptic RAP Charts: The 300mb chart shows High Pressure offshore producing a NW flow pattern aloft over the entire State of CA. A 110kt Jet Stream is diving SE into central WA, heading into ID. The 500mbchart shows a weak NW flow pattern over CA with -14°C temps and 576dm heights over Arcata to Tahoe and 582dm heights SW of San Diego. The 700mb Freezing Line runs from Arcata to Mt Shasta to Sierraville, with +6°C temps into the Imperial Valley. The flow pattern at this level of the atmosphere is from the NW up to 15kts. Most of CA is covered with 0.3 inch PWAT moisture with 0.4 inches from the Bay region N and NE. This dry air will allow for large diurnal swings in temps with chilly nights and mild afternoons, with some new record max temps possible. With a MSLP of 1028mb High Pressures across UT versus 1016mb near Imperial providing a generalized NE offshore flow pattern at the surface with light winds over the SJV with weak Santa Ana conditions for SOCAL. Freezing Levels over CENCAL today are up to 12,100ft, 12,100ft on Wednesday, 11,400ft on Thursday, 11,200ft on Friday, 11,600ft on Saturday, 12,000ft on Sunday.
FORECAST SUMMARIES
Days 1-7;
Tue, Dec 31st NEW YEARS EVE; the resilient High Pressure ridge anchored near the West Coast intensifies and steepens, with the active storm track moving a long-fetched Atmospheric River (AR) into BC, Canada and the southern Alaskan panhandle, with heavy/warm rains trailing SW to the Dateline at 25N. Several disturbances are imbedded in the westerly flow pattern across the WPAC. Fair/mild conditions continue over CA with SJV temps in the upper 60°’s to lower 70°’s with record-setting heat, and partly cloudy skies passing thru NORCAL. Overnight mins dip down to 26° at the coldest SJV Stations. The year ends with historic record-setting dryness for many official Stations in CA, which shatter the previous records!
Wed, Jan 1st HAPPY NEW YEAR; the strong resilient 576dm High Pressure moves onshore over the West Coast and into western Canada. The ridge builds northward into the Yukon, Canada, with the heavy AR warm rains continuing into southern Alaska, the BC, Canada and WA coastal regions along the western flank of the ridge. CA remains tranquil, fair and mild with a weak NE flow pattern and some cloudiness over NORCAL. Overnight the warm rains spread down to southern OR, then trail to the SW to a Low Pressure trough developing north of Hawaii. In addition to the WPAC AR, a new subtropical plume of moisture erupts at 140W and flows northward, attaching to the main AR that is already flowing into Vancouver and WA. SJV temps range from the upper 60°’s to lower 70°’s withrecord-setting heat possible, as minimums dipping as low as 27°/28°
Thu, Jan 2nd As the offshore High Pressure flattens a vort disturbance approaches the Olympic Peninsula producing heavy rains into WA. The warm AR rains spread thru OR, with partly cloudy skies reaching NORCAL. The trough north of Hawaii develops into a strong Low Pressure storm near 40N 160W, which pulls a subtropical plume of moisture northward at 140W that flows into the AR moisture plume which is traveling into Vancouver and the PACNW. Overnight High Pressure once again noses northward and severs the AR moisture feed into the PACNW. Fair skies continuing over CENCAL produce max temps into the upper 60°’s with the hot spots reaching 70° and minimum temps dipping as low as the upper 20°’s and lower 30°’s.
Fri, Jan 3rd A split flow pattern develops in the mid PAC basin near 160W with a mid Low Pressure anchoring the southern branch split, with the northern branch Jet Stream traveling thru southern Alaska. The southern branch Jet Stream is aimed near Hawaii at 110kts from the NW and continues to reach eastward toward 140W. High Pressure offshore west of CA blocks all storm activity northward into southern Alaska and the BC, Canada coastline with heavy rains. Fair skies and mild temps near persistence continue over CENCAL with a northerly flow aloft developing over CA. SJV Temps range into the 60°’s with mins down as low as 30°
Sat, Jan 4th The resident and very resilient 576dm High Pressure ridge moves over CA and to the NW, with a NW flow pattern developing over the PACNW as cold air slides down the eastern flank of the ridge down thru BC, Canada and a broad trough digs SW into the Midwest States. The large Low Pressure trough at 40N 150W continues to pump up a subtropical plume of moisture along 140W which travels northward partially wrapping around the storm center and partially tearing away and moving toward the Vancouver and Olympic region while CA remains fair/dry with SJV temps in the 60°’s and mins down to 28° at the cold spots.
Sun, Jan 5th The mega ridge extends from west of CA, NW into the North Pole region with ARCTIC air spilling southward along the east flank of the ridge into central Canada and then dives southward into the CONUS with the base of the ARCTIC trough reaching the SE States! The large storm system in the mid PAC continues to influence the subtropical plume of moisture erupting from the ITCZ at 140W, flowing northward with some of that moisture reaching the BC, Canada coastline and the bulk of the moisture wrapping into the main storm circulation moving into southern Alaska. CA remains fair/mild and dry with SJV temps cooling slightly.
Mon, Jan 6th The High Pressure ridge moves onshore over the West Coast with minor vort disturbances moving into western Canada carrying a long-fetched Atmospheric River of moisture into the Alaskan peninsula and BC, Canada, spreading southward to southern OR, as the subtropical moisture plume erupting at 140W flows toward NORCAL. Partly cloudy skies and showers reach the NW coastal region. CENCAL remains mostly fair/mild and dry.
Days 8-16, Long Range into Fantasyland Outlook; Day 8 begins;
Interesting notation; the GFS suggests a Tropical Cyclone development in the WPAC around Jan 11th. Models have been suggesting this feature for several days so it has growing confidence. By Jan 12th the GFS suggests that the Tropical Cyclone will begin to transport copious amts of moisture northward into the westerlies. The infusion of energy and moisture into the Westerlies generates a long-fetched Atmospheric River crossing the PAC basin with the moisture flowing into southern Alaska and BC, Canada. The end of the Fantasyland GFS forecast charts on Thu, Jan 16th shows the Tropical Cyclone dissipating with the remnant moisture field attached to the long-fetched Atmospheric River, feeding high PWAT moisture content across the entire PAC basin into the Alaskan Panhandle and western Canada.
Tue, Jan 7th shows weak High Pressure nosing over CA as a weak front dies out as it reaches into NORCAL, with the impressively long AR reaching across the entire PAC basin from the ITCZ at 140E NE all the way to southern Alaska down to WA with heavy warm rains. The position of the ridge nosing over NORCAL creates a NE flow pattern over CA with a few clouds spilling over the ridge into NV.
Wed, Jan 8th shows the long-fetched AR still flowing across the PAC basin with torrential flooding rains pounding the BC, Canada coastline, as High Pressure creates a north flow pattern over CA with partly cloudy skies reaching into NORCAL.
Thu, Jan 9th shows High Pressure dominant offshore west of CA, with a zonal westerly moist flow stretching across the PAC basin from Japan to BC, Canada, with the downwind flank of the ridge carrying some moisture into parts of NV while most of CA has an offshore NE flow pattern.
Fri, Jan 10th shows 576dm High Pressure over all of CA, with an clockwise circulation producing an offshore flow over SOCAL. The moist zonal westerly flow continues across the PAC basin with several disturbances imbedded within the flow aiming for BC, Canada.
Sat, Jan 11th shows a lull in the storm activity over the GOA with a disturbance moving eastward thru BC, Canada and partly cloudy skies over far NORCAL, with an offshore flow over SOCAL.
Sun, Jan 12th shows the redevelopment of strong High Pressure offshore west of CA rebuilding northward into the GOA and southern Alaska at 140W, with the resurgence of colder air diving southward thru western Canada into ID. Fair/mild/dry conditions continue over CA.
Mon, Jan 13th shows the High Pressure ridge alignment north/south at 130W with cold air diving southward into TX! CA remains fair/mild/dry, while the storm track is displaced northward into the Alaskan panhandle and southern Alaska and clearing skies spread across BC, Canada. A north flow pattern develops over CA.
Tue, Jan 14th shows High Pressure moving onshore over CA/OR/WA, with rains returning into BC, Canada. CA is very quiet with a 582dm High Pressure center located west of Pt Conception.
Wed, Jan 15th, shows the strong mega High Pressure ridge moving onshore over the West Coast, with a 582dm center nearing Pt Conception with CA maintaining fair/mild/dry conditions and the storm track displaced well to the north into the Alaskan panhandle region.
Thu, Jan 16th, the end of the Fantasyland GFS forecast charts shows impressively strong 582dm High Pressure intensifying over most of CA with warming temps and dry conditions continuing. Meanwhile, a large trough is locked into place mid PAC with the moisture feeding in a long sinuous curve originating from the ITCZ at 160E moving northward into the westerly flow and then traveling NE into BC, Canada.
TEMPS
NEW RECORD TEMPS
Station New Record Old Record__
Merced 63° 61° set in 1999
Madera 64° 58° set in 2003
Hanford 66° 61° set in 2003
Fresno 67° (Ties) 67° set in 1904 (A 109 year old record!)
Oakland Dwntwn 64° 63° set in 1997
San Jose 66° (Ties) 66° set in 1958
SAC Exe 62° 61° set in 2011
SAC Dwntwn 62° 61° set in 2011
Paso Robles 74° 71° set in 2000
SJV Min Temp highlights this morning include the following 22 Stations which reached CRITICAL Temps of 28° or below; 28° at Porterville, Lindcove, New Columbia, Cow Camp, Cal Farms, Lost Hills, Scofield, Cuber, Alpaugh, Shafter, Buena Vista Lake, 27° at Gustine, Fowler, Orange Cove, Sanger, Belridge, Orosi, Exeter, Tulare Lake, Kern Lake, 25° at Kesterson, Lindsay
SJV Max Temp highlights yesterday afternoon include the following; 74° at Lemon Cove,, Fountain Springs, Trimmer, Jasmine, Scofield, Cal Farms, Lindsay, Ivanhoe/Rayo, 75° at Strathmore, Lindcove, Terra Bella, Kern Cyn Powerhouse, 77° at A.G. Wishon Powerhouse, 78° at Ducor, Sherwood.
Minimum Temps this morning at the Paramount Citrus Stations ranged from the coolest minimum of a 27° at Orosi and Belridge, rising to the warmest minimum of 35° at Loma.
Maximum Temps yesterday afternoon at the Paramount Citrus Stations ranged from the coolest maximum of 66°at Horizon and Root Creek and rising to the warmest maximum of 78° at Ducor.
PRECIPITATION FORECAST
Day 1 – 5 QPF:
At 12Z (9am) Tuesday thru the period day Saturday night (Sunday @4am) shows; Tue/Wed/Thu/Fri/Sat shows all of CA DRY.
5DAY ACCUMULATION CHART:
Days 6 & 7 QPF thru next Sun/Mon shows light amts of precip over NORCAL with up to 0.2 inches, with light amts spreading into the northern portion of CENCAL.
16-Day QPF estimates (from the 12Z GFS) for;
Days 1-8 shows CA remains mostly DRY, with light precip >0.2 inch for NORCAL with some precip spreading into the northern portion of CENCAL.
Days 9-16 shows CEN/SOCAL remaining DRY with up to 0.2 inch for the far NW Coastal region.
0Z Operational GFS 384hr, 16Day QPF Chart; showing most of CA bone DRY thru Thursday, Jan 16th!
SATELLITE
Water Vapor 4KM Image of the West Coast at 8am Tuesday, December 31, 2013, shows a weak frontal boundary moving thru NORCAL into CENCAL along a dissipating cold front. A few high clouds are passing thru CENCAL.
Visible Satellite Image of the CA at 8am Tuesday, December 31, 2013, shows a weak decaying frontal boundary passing thru the Bay region which is quickly dissipating.
If you have any questions please call or text at any time of day or night.
Comments and suggestions always welcome.
Atmospherics Group International
Dan Gudgel Steve Johnson
559-696-9697 559-433-7316
used by permission