Regarding ground water pumping issues…at the bottom of the page please read an interesting article authored by UC Irvine professor James Famiglietti ; “Op-Ed: Just How Bad Is California’s Epic Drought?”
We have been tracking the WPAC Tropical Disturbance for a while and it still exists on today’s forecast charts. Global scale charts show a Tropical Cyclone developing in the WPAC on Feb 27th, near 10N 150E with sluggish directional motion. While the Tropical Cyclone spins around it manages to cast off a vast moisture field to the north which becomes fully entrained into the westerly flow pattern and into a developing MidPAC storm system as it crosses the Dateline on Feb 27th. By the 28th the PAC basin has 3 separate storm systems imbedded within the westerly flow pattern, including the developing storm which has crossed the Dateline and is fully attached to the Atmospheric River (AR) that is being generated by the Tropical Cyclone. On Mar 1st as the Tropical Cyclone appears to weaken, the AR attachment with the PAC storm system remains well supplied by the subtropical plume, although somewhat weaker which passes over Hawaii. By Mar 2nd the leading edge of this moisture finally reaches the West Coast and produces generous rainfall into the PACNW and into NORCAL. The weakened Tropical Disturbance remains stationary and begins to reload the local SW PAC region with high PWAT’s, again. As the Long Range charts indicate that this storm does indeed eventually reach CA on late Sun, Mar 2nd it spreads light rains into CENCAL on Mon Mar 3rd.
Mild spring-like, dry conditions with temps +12° above average will persist thru early next week under the influence of High Pressure. The dry air over the region and the mild temps will keep fog formation to a minimum. As previously advertised, a long awaited pattern change next week is expected to provide CENCAL with a much needed soaking storm period. Although details and timings issues still show some fluctuation, the general trend is indicating a very wet storm to reach CA at the end of the month which produces up to 3-4 inches of precip for the Sierra near YNP and up to 1.5 to 2 inches for the northern portions of the SJV diminishing to about 0.25 to 0.5 inch into the Kern portion of the SJV. The first disturbance arrives Wed with light rains in the lowlands and snow for the Sierra, with a stronger/wetter storm arriving Friday which winds down early Saturday. This storm has the potential to produce CENCAL’s first widespread heavy rain event of the season, with prolific snow production for the Sierra of 3 feet or more. Initially high snowlevels lower late Friday as cold air aloft advects into the region, which could also produce Thunderstorms in the SJV after frontal passage. Timing of frontal passage will be of critical importance for Thunderstorm development on Friday which are most favorable north of Fresno. Depending upon how fast the system departs on Saturday, convection could also fire up on Saturday, but may not be as strong as those that erupt on Friday. Hail is the primary concern for the Ag Districts. Models are still somewhat uncertain with how the storm evolution proceeds on Friday…with some models again suggesting that the storm splits and the bulk of precip and energy head for SOCAL. So this storm event needs to be monitored closely. It has or had the potential to be the biggest storm of the Season for the Southern Sierra with up to 1-3+ feet or more of snowfall at the higher elevations above 7,000ft with gusty winds to 60mph along the Crest. The forecast for Thunderstorms on Fri has many qualifications which must be set forth during next few days, but this is an early call that convective conditions appear favorable for Friday in the North Valley region. Longer range outlooks by the GFS show another possible storm system arriving into CA on MonPM, Mar 3rd which could bring the SJV another 0.25 inch, and the GFS Fantasyland Forecast shows a low confidence, warm/wet storm arriving on Day 16, valid on Mon, Mar 10th.
PRECIP past 24hrs over NORCAL; none
Sunday’s current 300mb Upper Jet Stream flow pattern for the EPAC, showing the infamous RRR High Pressure ridge offshore built up into Alaska, with a deepening trough of Low Pressure digging SE from the Aleutians. Very warm air is traveling over the top of the ridge thru the Bering Sea into the Arctic Ocean, then after chilling, is dropping southward thru Canada into the Midwest USA with subfreezing temps. This blocking pattern is the reason that CA continues to remain dry and warm. That is about to change as the “westerly flow” will eventually reach the West Coast on Wednesday thru Saturday. Arrows depict the flow pattern of the Upper Jet Stream
NCEP Chart depicting temp anomalies forecast for next Friday, February 28, 2014. The chart shows both warm and cold anomalies at the end of both scales of warmth and coldness with a +14° warm anomaly over northern Alaska and a -16° cold anomaly over southern Canada and the upper Midwest. Yes, this is a wild winter!
FORECAST SUMMARIES
Days 1-7;
Sun, Feb 23rd The RRR High Pressure ridge axis runs northward from offshore the West Coast up into Alaska and the Yukon with a strong 558dm High Pressure cell over the Alaska/Yukon border, as the mid-section of the ridge gradually pinches off and allows the southern branch Jet Stream to punch thru the ridge, bringing some warm/light rains into the WA/OR coastline, while providing abundantly sunny skies over CA with above average temps for another day. Overnight the ridge axis moves onshore over the West Coast as Low Pressure a Low Pressure trough digs SE from the Aleutians toward 40N 140W… and the westerly flow pattern begins to open the storm door into the PACNW and NORCAL.
Mon, Feb 24th The basic feature of the RRR High Pressure ridge axis remains over the West Coast and built up into Alaska. However, the mid-section of the ridge is becoming fully contaminated with moisture as the southern branch Jet Stream brings increasing warm air advection rainfall into the PACNW and just missing Crescent City, CA. A large trough continues to carve out in the GOA down to near 30N 135W with an abundance of moisture flowing across the PAC basin at low latitudes into the base of the trough. While the mean position of the High Pressure ridge maintains its axis over CA, the mid section of the ridge located over the PACNW is contaminated with warm advection moisture. Overnight as the trough continues to approach the West Coast, the ridge axis steepens and a southerly flow pattern develops ahead of the approaching storm system.
Tue, Feb 25th The RRR High Pressure ridge shifts eastward into the Great Basin, as the large trough begins to move onshore with a south to southeast flow ahead of the storm. There are a series of 3 disturbances rotating around the base of the trough at very low latitudes with the first two being possible significant rain/snow producers for CA and the third is colder and slightly dryer. As the moist south to southeast flow pattern develops well ahead of the storm, increasing clouds occur over NORCAL and perhaps a few showers reach into Cape Mendocino as partly cloudy skies prevail over CENCAL and fair skies continue over SOCAL. Overnight the High Pressure ridge continues to shift slightly east into the Great Basin which allows the offshore storm circulation to finally being moving onshore into NORCAL with rainshowers arriving with a south to north directional component due to the negatively tilted trough configuration.
Wed, Feb 26th As High Pressure continues to shift into the Great Basin, the warm/moist flow pattern spreads into CA with an approaching alignment running from N-NW to S-SE, so it spreads over the Coast Range of NOR/CENCAL about the same time with heavy rains along the Coastal region from Crescent City to Vandenberg, with lighter rainfall rates spreading inland into the SJV and eventually the Sierra…but it’s a slow process due to the trough configuration favoring a southerly flow instead of a SW flow pattern which would bring precip into the interior much quicker. The heavy rainfall is aided by a shortwave 500mb vortmax which pivots NE offshore, but is close enough to produce dynamic forcing with resultant heavy rains especially from Monterey northward along the coast. The secondary disturbance organizes further west, and is nearing 140W, and is attached to a reasonably strong cold front with charts depicts a narrow but dynamically strong frontal boundary. With the approaching systems originating from the subtropics, the snow levels into the Sierra will be initially high, at or above 7-8K, then lowering. QPF’s for the SJV run from near 0.5 inch at Stockton to 0.4 at Madera to
Thu, Feb 27th Temporary High Pressure moves onshore over CA, in between the departing storm and the approaching second storm. The negatively tilted trough and cold front approach the coast overnight, with heavy rains depicted by charts supplied by 1.25 inch PWAT’s initially moving into the Bay region first. The SW flow aloft at 500mb veers more southerly at 700mb which provides sufficient orographics for the Sierra, (but not the most ideal directional component). Overnight the heavy rains along the Coast Range very slowly spread eastward. Charts indicate the cold front with this system is impressive. While our immediate focus is upon the closest storm, also mentionable is a powerful Mid-PAC storm system which is attached to a long-fetched Atmospheric River (AR) that is supplied by a Tropical Disturbance in the Equatorial Region of the WPAC which we have been mentioning for quite some time.
Fri, Feb 28th Charts for Friday have evolved into a more dynamically driven storm system than has been previously illustrated, with the GFS suggesting a double-barrel Low Pressure negatively tilted trough with a -24°C cold core moving onshore into CA accompanied with a strong cold frontal passage which is aligned NW to SE instead of NE to SW with prefrontal warm sector PWAT’s This means that the storm will advance into the region from the west all at once, rather than the traditional approaching cold front moving SE through the region gradually. Vort dynamics associated with the cold front are in the upper medium spectrum range with much of the energy focused upon the Pt Conception region and then as evening approaches the energy swings into SOCAL. With FROPA an important element in the forecast, the post frontal environment appears favorable for Thunderstorms to develop over the Great Valley especially north of Fresno. Currently “timing” is the key, because if the FROPA occurs too late then chances of Thunderstorms decrease. Hail is the primary threat. The convective event will be within the limitation of the 84hr detailed Convective forecast charts on Tuesday for a better look. QPF charts shows this storm could be the best of the season thus far for snow production in the Sierra (if it does not split), with up to 2-3+ feet possible into the higher terrain and a SNOW DUMP for the Sierra Ski Resorts. The SW flow following FROPA will keep a moist onshore SW flow pattern advecting additional showers into CA overnight with snowlevels dropping significantly.
CAUTION: Some of the forecast charts have been flip/flopping on splitting the Friday storm into 2 sections with the southern portion taking the bulk of energy southward into SOCAL. This should be recognized as a potential fly-in-the-ointment for the Friday storm. Here is a chart example of how the split may occur…if it does;
Sat, Mar 1st The bulk of the wet storm system has past. With flat pressures offshore a moist westerly flow continues to bring additional showers onshore with orographics continuing into the Sierra. Depending upon skies coverage, conditions are again favorable for a chance of afternoon Thunderstorms throughout the region but only if there is enough clearing to allow for diurnal heating to destabilize the atmosphere. Overnight clouds and rains diminish and skies become partly cloudy. Another disturbance with a significant subtropical Atmospheric River (AR) approaches NORCAL which trails SW to Hawaii. Further west the zonal-type westerlies continue to flow near 40N with several imbedded disturbances crossing the PAC basin
Special Notation;
Days 8-16, Long Range into Fantasyland Outlook; Day 8 begins;
Sun, Mar 2nd shows a weak High Pressure ridge axis moving over the West Coast, followed quickly by a strong/moist SW flow pattern bringing the next storm system into the PACNW and NORCAL down to Ukiah to Tahoe. Skies over CENCAL are partly cloudy and SOCAL is fair and dry. Overnight the approaching shortwave pivots NE as the moisture field reaches onshore into the CA coastline with rainshowers from SFO northward.
Mon, Mar 3rd shows the trough axis moving thru CA with a weakening frontal boundary bring moderate rains into NORCAL and showers into CENCAL with up to 0.25 inch for wet spots in the SJV and 0.5 to 0.75 inch for the Southern Sierra. Overnight weak High Pressure moves onshore as the disturbance moves into the Great Basin. Further west a westerly zonal-type flow pattern stretches from Japan eastward to near the West Coast which is carrying a long-fetched Atmospheric River (AR) that originates from a Tropical Cyclone in the WPAC near 10N at 145E. This feature has been long advertised with varying timing issues but is still on the charts but much less intense than previously advertised by the GFS and is described in more detail above within the Special Notation.
Tue, Mar 4th shows weak High Pressure nosing into CEN/SOCAL with the moist onshore westerly flow pattern continuing into the PACNW and NORCAL. Partly cloudy skies exist over CENCAL.
Wed, Mar 5th shows a strong zonal, westerly flow pattern continuing to race across the PAC basin with several imbedded disturbances traveling eastward toward the West Coast. The leading storm plows into OR coastline with heavy rains which reach as far south as Cape Mendocino with weak High Pressure maintaining dominance over CEN/SOCAL. Overnight High Pressure begins to rebuild offshore west of SOCAL which begins to shunt the storm track back to the north.
Thu, Mar 6th shows 570dm High Pressure surging northward over CA with a dry NW flow pattern for CEN/SOCAL, while the moist westerly flow pattern continues to bring light rains into NORCAL. Overnight a new plume of subtropical moisture erupts from the ITCZ near 145W, flowing northward to 30N as an approaching storm traveling along the zonal flow at 160W begins to near the erupting plume.
Fri, Mar 7th shows the convergence of the storm system at 45N 150W with the newly erupting subtropical moisture plume, forming a new Atmospheric River (AR) which feeds an ample supply of moisture into the storm. Overnight High Pressure near the West Coast rebuilds which slows the eastward progression of the storm system.
Sat, Mar 8th shows the High Pressure ridge migrating over CA, with the fully charged AR approaching the West Coast still attached to the erupting moisture plume at the ITCZ at 140W. Further west the zonal westerlies continues to plow across the entire PAC basin uninterrupted by any ridging until the flow reaches 130W, near the West Coast. Overnight the High Pressure ridge shifts east which allows the N-S aligned AR to reach the NORCAL coastline with heavy rainfall.
Sun, Mar 9th shows the High Pressure ridge moving into the Great Basin which opens the storm door for CA as the diminishing AR pushes thru CA producing mod rains into NORCAL and lighter rains into CENCAL. This is rapidly followed by the well established moist zonal-type westerly flow pattern with increasing rainfall rates into NOR/CENCAL. The zonal westerly flow is being powered by a 160kt upper Jet Stream that is screaming across the PAC basin heading east.
Mon, Mar 10th shows a weak shortwave trough enhancing the dynamic lift over CA which increases rainfall into heavy intensities for NOR/CENCAL, accompanied by high snowlevels, just as the slightly weakened Jet Stream at 140kts noses into the CENCAL coastline. What a way to end the Fantasyland Forecast realm with a warm/wet zonal flow pattern and strong upper Jet Stream dynamics knocking at the doorstep. However this event has a very low confidence level as previous model runs do not indicate this evolution.
Special Notations;
It is noteworthy that Phoenix has yet to measure any rainfall for 2014 and that rainless streak may come to an end by the end of the coming week as one of if not the most potent storm system of the Season arrives on Friday. Models continue to remain persistent in weakening the RRR High Pressure ridge mid week with the first impulse arriving Wednesday and bringing widespread light to occasional moderate rainfall to CA, especially in the north. Amts over CENCAL will taper off dramatically to the south with this first system. Southern Sierra could see up to 1 ft of snowfall from the first storm in the northern region near YNP. A brief break can be expected on Thursday as the first storm departs to the east. Meanwhile a second stronger/wetter storm arrives into the CA coast on Friday with possibly the most significant widespread rain and snowfall of the Season. QPF have been inching upwards in the latest QPF charts illustrated below ↓. Since the storm has tapped into a deep subtropical source, rainfall efficiencies should be fairly high and as colder air advects late Friday the snowlevels drop. 2 feet or more of additional snowfall should occur in the Southern Sierra from YNP to Mammoth Mt. With the latest 7 Day QPF chart showing up to 3.8 inches for the YNP region, we could expect between 3-4 feet of snowfall into the upper Tuolumne and Merced River basins and nearby Mammoth Mt Ski Resort. Gusty S to SW winds will accompany Friday’s storm which is probably going to kick the “RAINSHADOW” affect into gear along the Westside SJV. This will make QPF estimates very problematic for the SJV, depending upon the strength and size of the shadowing from the Coast Range along the I-5 corridor. All QPF models from all sources are showing the rainshadow which gives high probability. Thunderstorms are appearing probable after FROPA on Friday, which is highly depending upon the ultimate timing of FROPA. The earlier FROPA occurs, the higher the probability of convection. With the strong dynamics aloft associated with this storm, certainly other convective parameters will be in place for the SJV late Friday afternoon and early evening and a more detailed look at the convective parameters will be examined as soon as the event comes within the 84hr time frame for convective modeling, but for now the set-up appears in alignment for at least the wording for Thunderstorms.
TEMPS
NEW RECORDS
Station New Record Old Record__
San Rafael 74° 73° set in 1995
Santa Maria 85° 80° set in 2002
Sandberg 70° 67° set in 2012 and 2002. This also extends the record number of Days at 70° or above to 6 Days, beating the previous record of 4 Days set in 1963
Wonder where the rainfall is going instead of CA? Here’s a clue;
RECORD EVENT REPORT
NATIONAL WEATHER SERVICE JUNEAU, ALASKA
…RECORD PRECIPITATION FOR JANUARY…
LOCATION NEW RECORD OLD RECORD YEAR SET YEARS OF OBS
JUNEAU AIRPORT 10.15″ 10.13″ 1985 1944-2014
EAGLECREST BASE 14.43″ 13.58″ 2013 2007-2014
PELICAN 24.71″ 22.33″ 1976 1967-2014
JUNEAU FORECAST OFFICE 11.79″ 9.99″ 2009 2001-2014
PRECIPITATION FORECAST
Day 1 – 5 QPF:
At 12Z (9am) Sunday thru the period Thursday night (Friday @4am) shows;
Sun shows CA DRY.
Mon shows CA DRY.
Tue shows light rains spreading into Cape Mendocino and into the Eel, Klamath, Smith, the western portion of the Shasta basin and down into the Russian River basin.
Wed shows the beginning of a wet period for CA with precip covering most of CA on the first day of the series. With up to 1.5 inches into the higher terrain of NORCAL from Cape Mendocino south to the Santa Cruz and Santa Lucia mts and thru the Shasta Lake region and then southward into the northern Sierra to near Tahoe, with up to 1 inch from the Smith River basin southward along the coast to SLO, Santa Barbara and Ventura Co, and from most of the Shasta River basin SE thru the Sierra down to near the Kings River basin, with up to 0.5 inch covering most of NORCAL and the SAC Valley down to Turlock/Merced in the SJV and into the Kaweah, Tule and upper Kern River basins in the Sierra, with 0.2 inch from near Chowchilla/Madera southward in the SJV down to Kettleman and near Delano and thru the Tehachapi mts and lower Kern River basins and into most of the LA basin, with >0.1 inch in a “Rainshadow” located into the southern SJV from Kern Co southward into the upper Mojave Desert region and the coastal section of SOCAL.
Thu shows >0.1 inch of precip along the Coast Range and thru the Sierra down to Isabella and also into the higher terrain of SOCAL. The Great Valley remains dry from Red Bluff to Kern Co.
5DAY ACCUMULATION CHART:
Saturday’s 7 Day QPF Chart; shows a precip focal point of 4.1 inches for the northern coast range east of Fort Bragg, with a focal point of 4 inches into the Santa Lucia’s and a focal point of 3.6 inches into the Stanislaus and Tuolumne River basins and also into the higher terrain of the San Gabriel mts. The graphic chart shows the SJV with a “Rainshadow” hole evident into the southern SJV. The Southern Sierra QPF’s range from the 3.6 inches in the north, diminishing to approx 1+ inch near Isabella.
Sunday’s 7 Day QPF Chart; showing up to 5.5 inches for the Santa Barbara coastline, 4.9 inches for the Central Coast and up to 3.8 inches for the Northern and Southern Sierra. The “rainshadow” is still evident into the SJV.
Close up of 7 Day QPF for CENCAL region depicting up to 4-5 inches for the Santa Lucia’s along the Central Coast, 3-4 inches for the Sierra from YNP into the San Joaquin River basin and generally about 2-3 inches into the Sierra down into the Tule and upper/western portion of the Kern River basin. A “Rainshadow” is consistently depicted along the Westside SJV from near Firebaugh southward to near Taft and Mettler in Kern Co with 0.25 to 0.5 inch.
16-Day QPF estimates (from the 0Z GFS model) for;
Days 1-7; shows up to 5.5 inches for the Santa Barbara coastline, 4.9 inches for the Central Coast and up to 3.8 inches for the Northern and Southern Sierra. The “rainshadow” is still evident into the SJV with QPF’s along the Westside SJV ranging from 0.25 to 0.5 inch with higher totals in the northern districts which diminish to the southern districts of Kern Co.
Days 8-16; shows 1+ inch for most of NORCAL, diminishing rapidly south with only 0.25 inch for CENCAL and dry conditions for SOCAL.
Saturday’s 0Z 9pm GFS 384hr, 16Day QPF Chart, depicting a very wet NORCAL and portions of CENCAL, with diminishing amts of rainfall reaching into the SW section of SOCAL while the lower deserts remain dry. With up to 5 to 6 inches for the NW Coastal region diminishing to 4-5 inches for a large section of NORCAL, with up to 3-4 inches in the Sierra from the Feather basin southward as far south as YNP and from 2-3 inches for the San Joaquin to Kings River basins, with diminishing amts into the Kaweah and Kern River basins. The interior of CENCAL QPF’s range up to 2 inches for the northern SJV, to about 1.5 inch for the Central SJV down to 0.5 inch or less for Kern Co. A rainshadow hole is observed into a portion of the Westside SJV, near Fresno Co.
SATELLITE
Water Vapor 4KM Image of the West Coast Saturday, February 22nd, 2014, shows a dry NW flow pattern aloft over NOR/CENCAL with very dry air slicing thru NORCAL. Some subtropical moisture is encroaching upon portions of SOCAL.
Visible Satellite Image of the CA Saturday, February 22nd, 2014, shows NOR/CENCAL abundantly clear with a few high clouds over SOCAL.
High Definition Resolution, full color detailed image of CENCAL showing lots of brown shades in the Coast Range and Sierra foothills, with the patches of green in some of the SJV Ag Districts. To enlarge the image, click into it and then pull the corners outward.
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
Op-Ed: Just How Bad Is California’s Epic Drought?
True progress will require a push for groundwater management.
(Photo: David McNew/Getty Images)
February 22, 2014 By James Famiglietti
James Famiglietti is a professor of earth system science and civil and environmental engineering at University of California, Irvine. He appeared in the documentary film ‘Last Call at the Oasis.’
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Four years ago, during an interview for the world water crisis documentary Last Call at the Oasis, I was blunt in my analysis of California’s water future. “Let me be abundantly clear about this,” I told the filmmakers. “California faces a water crisis of potentially epic proportions. How we respond today will define who we are tomorrow.”
At the time, the Golden State was at the tail end of a multiyear drought. Beginning in 2006 and continuing through 2010, the Sacramento and the San Joaquin river basins lost more than 30 cubic kilometers of freshwater—nearly equivalent to the volume of Lake Mead at capacity. Two-thirds of this loss resulted from pumping groundwater from beneath the Central Valley to irrigate the crops that supply our state and our nation with food.
So, how far has the state come since 2010? Let’s just say this: My Last Call interview could have been recorded only yesterday.
Fresh off one of the driest years in its history, California is poised to enter its next great epoch of groundwater depletion. The state’s drought is worse than most if not all past ones. State Water Project and Central Valley Project surface water allocations have been slashed to nothing. Farmers are digging more wells. We could easily drive our groundwater levels to historic new lows, with little long-term chance for recovery.
Even if the state legislature passes a $700 million drought relief package proposed by Gov. Jerry Brown earlier this week, the state—as evidenced by new monitoring from NASA’s GRACE satellites—still has a long way to go to mitigate the worst effects of its prolonged drought.
Using the satellites to monitor monthly water levels (snow, rivers, lakes, reservoirs, water in soils, and groundwater) in the Sacramento and San Joaquin river basins from March 2002 through December 2013, my colleagues and I at the University of California Center for Hydrologic Modeling have discovered three alarming trends;
First, total water storage is at its lowest point since the GRACE satellites began collecting data in 2002.
Second, in the last few years, total water storage has declined by more than 25 cubic kilometers. On an annual basis, that is more water than all Californians use for domestic, municipal, and industrial needs (or all the water that is not used to grow food or to maintain environmental health).
Third, California is arguably in the midst of a long-term dry spell that stretches at least as long as the 12-year life span of the GRACE mission. It has been punctuated by a few wet years, such as 2006 and 2011, but are we really looking at a long, steady decline in freshwater availability?
For California to make true progress toward securing its water future, it must act today to actively manage groundwater. The $700 million emergency plan proposed by Governor Brown is a much needed step in the right direction, and the state legislature should enact it as soon as possible. Medium- to long-term legislation, however, must be proactive and include significant provision for drought research, including enhanced monitoring and forecasting tools.
It will be easy to become distracted by the good fortune of the next big snowstorm, or even by the occasional wet year.
We need, however, to get something done now, so that in another four years, we don’t look back and question just how far have we come.
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