Looking around the web for some kind of sign that Winter might miraculously appear on the West Coast, I found this Sacramento Bee story on our La Niña. The tone, or basic climate assumptions displayed by the reporter (and the editor...do newspapers still employ editors?) really fired me up! NOAA's "Year for the Record Books" isn't as scary as it sounds...Irene was the only hurricane to qualify in the Billion Dollar Club, most of the events are Springtime tornado outbreaks.
Incredibly, the reporter likens our "Pineapple Express" to hurricanes! By definition hurricanes are circular, well organized storms...think our weather makers on steroids.
There is hurricane news: We're enjoying a period of low intensity Atlantic Tropical Cyclone activity. In fact each day that passes sets a new record for Days Without a Major Hurricane landfall on the United States.
This is born out by the historical reanalysis by NOAA of the hurricane records. No December forecast for next season's Hurricane Season was issued, and Colorado State University is not defending the long range models anymore. They noted:
"We strongly believe that the increases in atmospheric CO2 since the start of the 20th century have had little or no significant effect on Atlantic basin or global Tropical Cyclone activity as extensively discussed in our many previous forecast write-ups and recently in Gray (2011). Global tropical cyclone activity has shown no significant trend over the past thirty years."
I cooled off and found another Long Period Cycle turning to the Cold Side:
AMO begins negative (cold) phase "This is the first time the November value has been negative since about 1996. It appears the down cycle has started. This portends a cooler period, especially winters."
La Niña will be weak to moderate through late Spring says NOAA's Climate Prediction Center's 90 Outlook issued today.
AO, the Arctic Oscillation is trending to the cold side, though NOAA has some problem with the data at present.
That's a lot of cold. It's probably bad news precip-wise. Cooler ocean temps mean less convection which is the pipeline that fills weather systems with moisture.
With my head filled with cool thoughts, I decided to stay awake to watch some actual falling snow. I watched the 10 O'clock and 11 O'clock News weathercasts...I watched Luc Besson's "The Fifth Element". Around 2AM I looked at the webcams and saw a little bit of dusting. I looked at my front porch...not a flake yet.
I fired up another SciFi Classic, Ridley Scott's "Blade Runner" on Blu-ray I must have fallen asleep around 3AM. I woke up and looked outside a 0430...still no joy. When I looked again, there was a little dust on things, but it wasn't snowing anymore. Blazing sunlight burned through my blinds at 0830. Chain controls were up over Donner Summit for a time, but they'd been lifted in time to cause enough spinouts to cause CalTrans to hold westbound traffic for a time.
I missed the last morning weathercast on the TrainWreck News, so I found one online.
Thanks Channel 8 KOLO Reno!
Showing posts with label MJO. Show all posts
Showing posts with label MJO. Show all posts
Thursday, December 15, 2011
Friday, November 18, 2011
Same New Story
Smoking gun:
LATEST GUIDANCE HAS TRENDED A LITTLE DRIER ON PRECIP AMOUNTS AND HAVE LOWERED QPF AMOUNTS TO REFLECT THIS.
CURRENTLY A BAND OF PRECIPITABLE SEEN IN AMSU SATELLITE SOUNDER IMAGERY STRETCHES INTO THE ERN PAC TO NEAR THE OREGON OF UP TO 1.25 INCHES. BUT THIS BAND IS MOVING SOUTH AND WILL NOT LIKELY INTERACT WITH THE THE UPPER TROUGH AND COLD FRONT. IN FACT MODEL PWATS FOR LATE TONIGHT AND
EARLY FRIDAY ARE ONLY ABOUT 0.45 INCHES OR LESS OVER THE REGION.
MOST RECENT STORM SYSTEM WAS OVER FORECAST IN TERMS OF PRECIP AMOUNTS SO THINK THIS ONE MIGHT BE AS WELL.
That's from the Reno NWS 4:21AM PST Thu Nov 17, 2011 Area Forecast Discussion (Italics C/P)...right from "the horse's mouth"
I'm upgrading "MOST RECENT STORM SYSTEM WAS OVER FORECAST IN TERMS OF PRECIP AMOUNTS SO THINK THIS ONE MIGHT BE AS WELL." from chatty 4:21AM remark to the "Season Trend" so far.
So, I made a point of watching the local 10 O'clock News...sure enough Bill Martin, KTVU2's WeatherDude talked about the system (which did produce sprinkles here at the Ancestral Digs around sunset) He ran the models on the screen, and said: "I don't believe it! The models say this system will approach our coast, then just dry up and move southward along the coast. Tune in tomorrow night and I'll have the whole story for you"
Curious, I clicked on the NWS Monterey/San Francisco AFD to see if any forecast trepidation was in evidence. There it was!
"FROM PREVIOUS DISCUSSION...THE NAM AND GFS MODELS TRENDED MUCH DRIER THE LAST 24 HOURS AND KEPT THE MAIN LOW AND ASSOCIATED RAINFALL OFFSHORE. THE ECMWF HAS DEVIATED LITTLE AND BRINGS THE CORE OF THE LOW AND RAINFALL OVER THE DISTRICT...FOCUSED MOST HEAVILY FROM SANTA CRUZ MOUNTAINS SOUTHWARD THROUGH COASTAL MONTEREY COUNTY OVERNIGHT SATURDAY INTO SUNDAY MORNING. THE CANADIAN MODEL (GEM) IS CLOSER TO THE ECMWF THAN THE GFS AND FORECAST WILL TREND WITH THE WETTER MODEL SOLUTIONS AND THE CNRFC QPF. THIS EVENT IS VERY SIMILAR TO THE VETERANS DAY RAIN AROUND HERE WHEN THE NAM/GFS MODELS DEPICTED A DRY SCENARIO WHILE THE ECMWF BROUGHT THE MAIN FRONTAL BOUNDARY ONSHORE. WILL HOLD ONTO THE WET FORECAST THAT WE`VE HAD OUT BUT WILL BE INTERESTING TO
WATCH THE VERIFICATION OF THE EVENT."
This really got me thinking...so far this season the storms model wet, then slow down, dry out, and "under-perform"...the steering seems at odds with the model runs when all is said and done as well. This is the second storm in the last month that caused the forecasters to make note of model "disagreements".
I'd love to talk to one of these Lead Forecasters! I'd like to know how their models are refined over the years. Now that we're well into the Negative Phase of the PDO, does this become a background assumption factored into the works of the model itself? Maybe it's just another set of data points that weigh on the model's prediction.
Who writes the models? Do frontline forecasters give feedback to the model gurus? How do the models evolve with the long period variability of our climate? What happens when meteorology discovers new climate mechanisms or confirms previously discounted contributing factors?
Models don't agree? The more I ponder this, the more questions I have. Throw in the alphabet soup of oceanic oscillations and I get a headache!
LATEST GUIDANCE HAS TRENDED A LITTLE DRIER ON PRECIP AMOUNTS AND HAVE LOWERED QPF AMOUNTS TO REFLECT THIS.
CURRENTLY A BAND OF PRECIPITABLE SEEN IN AMSU SATELLITE SOUNDER IMAGERY STRETCHES INTO THE ERN PAC TO NEAR THE OREGON OF UP TO 1.25 INCHES. BUT THIS BAND IS MOVING SOUTH AND WILL NOT LIKELY INTERACT WITH THE THE UPPER TROUGH AND COLD FRONT. IN FACT MODEL PWATS FOR LATE TONIGHT AND
EARLY FRIDAY ARE ONLY ABOUT 0.45 INCHES OR LESS OVER THE REGION.
MOST RECENT STORM SYSTEM WAS OVER FORECAST IN TERMS OF PRECIP AMOUNTS SO THINK THIS ONE MIGHT BE AS WELL.
That's from the Reno NWS 4:21AM PST Thu Nov 17, 2011 Area Forecast Discussion (Italics C/P)...right from "the horse's mouth"
I'm upgrading "MOST RECENT STORM SYSTEM WAS OVER FORECAST IN TERMS OF PRECIP AMOUNTS SO THINK THIS ONE MIGHT BE AS WELL." from chatty 4:21AM remark to the "Season Trend" so far.
So, I made a point of watching the local 10 O'clock News...sure enough Bill Martin, KTVU2's WeatherDude talked about the system (which did produce sprinkles here at the Ancestral Digs around sunset) He ran the models on the screen, and said: "I don't believe it! The models say this system will approach our coast, then just dry up and move southward along the coast. Tune in tomorrow night and I'll have the whole story for you"
Curious, I clicked on the NWS Monterey/San Francisco AFD to see if any forecast trepidation was in evidence. There it was!
"FROM PREVIOUS DISCUSSION...THE NAM AND GFS MODELS TRENDED MUCH DRIER THE LAST 24 HOURS AND KEPT THE MAIN LOW AND ASSOCIATED RAINFALL OFFSHORE. THE ECMWF HAS DEVIATED LITTLE AND BRINGS THE CORE OF THE LOW AND RAINFALL OVER THE DISTRICT...FOCUSED MOST HEAVILY FROM SANTA CRUZ MOUNTAINS SOUTHWARD THROUGH COASTAL MONTEREY COUNTY OVERNIGHT SATURDAY INTO SUNDAY MORNING. THE CANADIAN MODEL (GEM) IS CLOSER TO THE ECMWF THAN THE GFS AND FORECAST WILL TREND WITH THE WETTER MODEL SOLUTIONS AND THE CNRFC QPF. THIS EVENT IS VERY SIMILAR TO THE VETERANS DAY RAIN AROUND HERE WHEN THE NAM/GFS MODELS DEPICTED A DRY SCENARIO WHILE THE ECMWF BROUGHT THE MAIN FRONTAL BOUNDARY ONSHORE. WILL HOLD ONTO THE WET FORECAST THAT WE`VE HAD OUT BUT WILL BE INTERESTING TO
WATCH THE VERIFICATION OF THE EVENT."
This really got me thinking...so far this season the storms model wet, then slow down, dry out, and "under-perform"...the steering seems at odds with the model runs when all is said and done as well. This is the second storm in the last month that caused the forecasters to make note of model "disagreements".
I'd love to talk to one of these Lead Forecasters! I'd like to know how their models are refined over the years. Now that we're well into the Negative Phase of the PDO, does this become a background assumption factored into the works of the model itself? Maybe it's just another set of data points that weigh on the model's prediction.
Who writes the models? Do frontline forecasters give feedback to the model gurus? How do the models evolve with the long period variability of our climate? What happens when meteorology discovers new climate mechanisms or confirms previously discounted contributing factors?
Models don't agree? The more I ponder this, the more questions I have. Throw in the alphabet soup of oceanic oscillations and I get a headache!
Sunday, October 23, 2011
Head Scratching Time Begins
A couple of things came streaming through my social sites today...more precisely, I noticed them today...
KCRA3's @MarkFinan's tweet touting his "La Niña Explainer" on the KCRA 3 Weather Facebook Page
I didn't know Finan had a weather page on facebook, so I searched and liked it. Here it is...it's a good thumbnail sketch of a seriously complex system:
"For those of you that didn't see my explanation of La Nina on the news last night, let me explain here. First the basics... La Nina refers to a period of cooler than average water in the equatorial Pacific. The cooler than average water can set or alter weather patterns for extended periods of time, like for a season.
Based on past episodes, there are tendencies that you can see when we have a La Nina in place. For some parts of the country, like the Southeast and the Pacific Northwest, those tendencies are pretty well defined. The Northwest has a very good chance of having a cool, wet winter. For our area the signals are very mixed.
Last year was a La Nina year and the water year was very impressive in NorCal. Sacramento finished with about 125% of average rain and the Sierra had about 200% average precipitation.
Not all years are like that for us. Some years come in pretty average and some come in very dry. 1975-76 was a La Nina season and was one of the driest years we have ever seen. Sacramento only picked up about 7 inches of rain that season, about 36% of average.
The problem is that there are more forces at work that [effect] the equatorial Pacific. There is the Arctic Oscillation, the North Atlantic Oscillation, the MJO, the PDO etc. All of these have some influence on our weather patterns at any given time. Research into these is ongoing so seasonal forecasting is still pretty iffy.
So the bottom line is we don't know what sort of Winter we'll have here in NorCal."
Our climate is like an onion in that there are many layers of driving forces that influence the climate in the long term and weather in the short term. You could call these drivers the "Alphabet Soup"...they are all acronyms: AO, ENSO, PDO, MJO, NAO for a start.
ENSO (El Niño Southern Oscillation) is like the onion's skin. It's on the surface and it's the first oscillation that casual observers discover, and it's the shortest period oscillation we've discovered. ENSO is home to El Niño and La Niña.
Mr Finan is right about the forecasting being "iffy", most of the dedevelopment of the computer forecasting models took place in the last 30 years or so...about the same time that the PDO was in the Positive Phase (read warm phase). Now that the PDO has crossed into negative territory, the models will have accuracy problems.
Clearly meteorologists haven't yet found the mechanism that drives Central California Precipitation during La Niña Winters.
Notice all the acronyms end with an "O" for oscillation. These are all cycles of temperature trends for different oceans or regions of oceans. Oceans are where the lion's share of Earth's heat is stored. Most of Earth's heat comes from the Sun, while a fraction comes from the Earth's molten iron core via vulcanism...see deep ocean vents for example.
The Sun has cycles too, though I'd wager we haven't discovered most of these yet. The most familiar cycle is the Sunspot Cycle. It's the first one we noticed. The earliest surviving record of sunspot observation dates from 364BC , based on comments by Chinese astronomer Gan De in a star catalog. The first clear mention of a sunspot in Western literature, around 300 BC, was by Theophrastus, a student of Plato and Aristotle.
I was 50 years old when I saw my first sun spot. I was on The New Seeker a "party boat", off the beach at Pacifica fishing for salmon. The marine layer was just the right thickness to reveal the disc of the Sun which was sporting a huge sunspot several times the size of the Earth.
Solar observers say the Sun is being very quiet, just another monkey wrench in the forecaster's bailiwick to complicate their job.
KCRA3's @MarkFinan's tweet touting his "La Niña Explainer" on the KCRA 3 Weather Facebook Page
I didn't know Finan had a weather page on facebook, so I searched and liked it. Here it is...it's a good thumbnail sketch of a seriously complex system:
"For those of you that didn't see my explanation of La Nina on the news last night, let me explain here. First the basics... La Nina refers to a period of cooler than average water in the equatorial Pacific. The cooler than average water can set or alter weather patterns for extended periods of time, like for a season.
Based on past episodes, there are tendencies that you can see when we have a La Nina in place. For some parts of the country, like the Southeast and the Pacific Northwest, those tendencies are pretty well defined. The Northwest has a very good chance of having a cool, wet winter. For our area the signals are very mixed.
Last year was a La Nina year and the water year was very impressive in NorCal. Sacramento finished with about 125% of average rain and the Sierra had about 200% average precipitation.
Not all years are like that for us. Some years come in pretty average and some come in very dry. 1975-76 was a La Nina season and was one of the driest years we have ever seen. Sacramento only picked up about 7 inches of rain that season, about 36% of average.
The problem is that there are more forces at work that [effect] the equatorial Pacific. There is the Arctic Oscillation, the North Atlantic Oscillation, the MJO, the PDO etc. All of these have some influence on our weather patterns at any given time. Research into these is ongoing so seasonal forecasting is still pretty iffy.
So the bottom line is we don't know what sort of Winter we'll have here in NorCal."
Our climate is like an onion in that there are many layers of driving forces that influence the climate in the long term and weather in the short term. You could call these drivers the "Alphabet Soup"...they are all acronyms: AO, ENSO, PDO, MJO, NAO for a start.
ENSO (El Niño Southern Oscillation) is like the onion's skin. It's on the surface and it's the first oscillation that casual observers discover, and it's the shortest period oscillation we've discovered. ENSO is home to El Niño and La Niña.
Mr Finan is right about the forecasting being "iffy", most of the dedevelopment of the computer forecasting models took place in the last 30 years or so...about the same time that the PDO was in the Positive Phase (read warm phase). Now that the PDO has crossed into negative territory, the models will have accuracy problems.
Clearly meteorologists haven't yet found the mechanism that drives Central California Precipitation during La Niña Winters.
Notice all the acronyms end with an "O" for oscillation. These are all cycles of temperature trends for different oceans or regions of oceans. Oceans are where the lion's share of Earth's heat is stored. Most of Earth's heat comes from the Sun, while a fraction comes from the Earth's molten iron core via vulcanism...see deep ocean vents for example.
The Sun has cycles too, though I'd wager we haven't discovered most of these yet. The most familiar cycle is the Sunspot Cycle. It's the first one we noticed. The earliest surviving record of sunspot observation dates from 364BC , based on comments by Chinese astronomer Gan De in a star catalog. The first clear mention of a sunspot in Western literature, around 300 BC, was by Theophrastus, a student of Plato and Aristotle.
I was 50 years old when I saw my first sun spot. I was on The New Seeker a "party boat", off the beach at Pacifica fishing for salmon. The marine layer was just the right thickness to reveal the disc of the Sun which was sporting a huge sunspot several times the size of the Earth.
Solar observers say the Sun is being very quiet, just another monkey wrench in the forecaster's bailiwick to complicate their job.
Friday, January 21, 2011
Becalmed
I do find myself a little underwhelmed tonight...the weather has reached monotonous territory around the Tahoe Sierra. I feel like I've been watching the midsummer weather on Bay Area TV...the very textbook definition of monotony...I even saw the telltale signs in Thursday afternoon's Reno AFD!
Searching in vain for a little meteo-stimulation, I looked at the January 90 Day Climate Outlook Discussion. Wadda know? All the new to me acronyms are there in black and white. Some of these weather discussions can be a little dry, and this one in particular is.
The sad thing is it's calling for continued dry weather, and calling the La Niña moderate to strong.
I jumped to the Northstar Weather Discussion Blog and found a tiny ray of hope. It seems the models are starting to suggest that the ridge over the West Coast may be retrograding soon. If the ridge moves west, temps will fall in the High Sierra, and the storm door may open again.
I guess you could say I'm feeling a little like I imagine a sailing ship's captain whose mighty sailing vessel is dead in the water, becalmed by the lack of tradewinds somewhere adrift in the Horse Latitudes.
I've surely been overstimulated by all the adrenaline producing early winter and late fall heavy weather. I miss my adrenaline! Not to mention my Hero Snow!
Searching in vain for a little meteo-stimulation, I looked at the January 90 Day Climate Outlook Discussion. Wadda know? All the new to me acronyms are there in black and white. Some of these weather discussions can be a little dry, and this one in particular is.
The sad thing is it's calling for continued dry weather, and calling the La Niña moderate to strong.
I jumped to the Northstar Weather Discussion Blog and found a tiny ray of hope. It seems the models are starting to suggest that the ridge over the West Coast may be retrograding soon. If the ridge moves west, temps will fall in the High Sierra, and the storm door may open again.
I guess you could say I'm feeling a little like I imagine a sailing ship's captain whose mighty sailing vessel is dead in the water, becalmed by the lack of tradewinds somewhere adrift in the Horse Latitudes.
I've surely been overstimulated by all the adrenaline producing early winter and late fall heavy weather. I miss my adrenaline! Not to mention my Hero Snow!
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