Archive for the ‘Drought’ Category

California – The wettest start since 2010… And more on the way
January 31, 2017

I’m getting asked a lot of questions about our weather.  Why are we getting so much rain?  Why is it a year delayed from last year’s strong El Nino?  Is the drought over? What’s going on?

sofarthisyear

Four months into the water year we have the wettest start ever recorded.

To answer these questions I first have to give some perspective on climate in California and probabilities.

In case you don’t know, California is a state of extremes when it comes to precipitation.  Throughout recorded history we’ve alternated between drought and excessive rain.  Los Angeles is a good example of these extremes.  While we average 15 inches of rain a year, we are rarely near this amount.  If you look at the past 30 years, we’ve gone from extremely dry years to well above average years.  In the end, it averages 15 inches.

30yearsrain

snowpack

Next snow survey is February 2nd and we’ll near 200%.

The one question that is a little more difficult to explain is the why we’re getting the heavy rain this year instead of last year.  Last winter we were prepared for the potential of heavy rain. The reason we thought this was because in all of the significantly strong El Nino climate patterns, Southern California got soaked.  The odds were in our favor.  But the rain didn’t come.

2015_Significant El Ninos

The 2015/16 water year only recorded 6.57″ of rain.

What is fascinating this year is we are in a weak La Nina or neutral weather pattern.  Both of these patterns slant dry for the state of California and especially for Southern California.  The probability our state would be dry this year is 70%, leaving a 30% chance we’d be above average.  And, if you really study this image, there isn’t a weak La Nina pattern that is well above average for Southern California.

laninaneutralpattern

Instead what we are seeing is the wettest winter since 2010.  The storms of the past two months have recouped 37% of the state’s five-year snow/water deficits. And for the first time since January 2014, no place in California is in an exceptional drought.  Precipitation is more than 200% of average and the Sierra Snow pack is looking great!

droughtupdate2016_snowpack_update

So what gives? Why the two extremes in outcomes?  I could give the answer, “That is how the weather works sometimes.” And this reply wouldn’t be completely wrong because even with an excellent forecast for a 90% chance of rain, there are days it’s dry.

But the answer is a little more complicated.

Last year the water was so warm in the Pacific that it affected the jet stream and moved all of the heavy rain to the Pacific Northwest and Northern California.

This winter we’ve been aided by numerous atmospheric rivers or a Pineapple Express.  This type of pattern can occur at any time regardless of an El Nino, La Nina or neutral pattern.  These rivers of atmospheric moisture are responsible for much of the devastating flooding in California’s history.  And it played a big part in the flooding on Jan. 22.

longbeachflooding

Long Beach received the most rain ever recorded in a 24 hour period, 3.97″.

ar

Most people don’t know about the mega flood of 1862, which was caused by an intense atmospheric river. It has a return period of 100-200 years, meaning it will happen again.

califlooding

And this leads me to climate change.  The latest research shows that in a warming planet, droughts will become more severe and heavy rain events will occur more often.  Before we started getting the rain in December, Southern California went through the driest five-year stretch ever recorded.  And, if you look at tree ring data, it may have been the driest stretch in 1,000 years.

record-dry2016_recorddry

But if you look at the history of flooding in California, intense flooding events occurred before the industrial age and atmospheric rivers are responsible for most of these events.  Attributing climate change to future flooding events may be hard to do.  Upcoming research will need to address how a warming world affects atmospheric rivers.

Going forward, the key for our drought, especially in Southern California, is we need this kind of winter pattern for two more years so we can get out of a drought cycle.  And, of course, I’ll keep you posted.

 

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Southern California is Making a Comeback!
February 24, 2016

euro

It’s the fourth quarter and SoCal is down by three touchdowns. The clock is ticking and 17 million people are wondering if this will be a disappointing finish.  Don’t give up yet, this is the rain forecast for Sunday and Monday with more on the way.

With one month to go before one of the strongest El Ninos on record fades, the question remains: How much more rain and snow is on the way, and why has Southern California been so dry?

2015_El Nino So Far

Let’s start by going back in time and look at the El Nino rain forecast for winter. A couple of things stick out. First, notice how Southern California, Texas and Florida are all forecast to receive an above average amount of rain. The Pacific Northwest is dry and Northern California is a toss up. All of the previously strong El Ninos showed no correlation to NoCal, it was 50/50.

SoCalBust

This is what has happened so far this winter. The bonus is most of the water sheds and reservoirs, which are located in Northern California and provide water for the entire state, are filling up. But Southern California has been incredibly dry, prompting people to ask: Where is El Nino? I call this forecast the 17-million person “bust.”

What is fascinating to me is what is happening this winter in the Pacific Northwest. Seattle, Washington and Portland have recorded their wettest winters ever! Record keeping goes back to 1894.  So the question is why.

SoFar

The El Nino-fueled moisture is in the Pacific, as predicted, but the jet stream has moved the rain into the Pacific Northwest and Northern California. The dry slot has been Southern California and Southern Arizona. But why is this blocking ridge of high pressure here?

Warmestwater

You’ve heard us say, “Every El Nino is different.” And that is certainly the case this year. The warmest water in the Pacific Ocean isn’t near South America like it was in previously strong El Nino patterns. The warmest water is farther west, south of the Hawaiian Islands.

RisingAir

That warmth is creating a large area of low pressure and rising air.

SinkingAir

In turn, the sinking air has created a large area of high pressure keeping the rain away from Southern California.

The rain is back in SoCal March 6th and the longer term climate models have a wet March but these same models also showed a furry of storms in February and obviously that hasn’t happened. So, what do you think will happen?  You can Tweet or Facebook me at: @anthonynbcla.

Time is running out, the clock is ticking and 17 million people are wondering if SoCal can make a come back.

El Nino & California
January 13, 2016

We are halfway though California’s wet season and in the three wettest months of the year. While we’ve been in an El Nino pattern since March, California doesn’t feel the effects of this climate pattern until late fall and winter.

2015_Snowpack_Update

The great news is Northern and Central California have been receiving a lot of beneficial rain and snow. In fact, our snowpack is more than double what it was last year at this time.  And some spots will get two more feet of snow in the next two days.  One-hundred percent is considered an “average” amount of snowpack for this date and we are right there. The below image is a comparison of the snow amounts on this date to January of 2014.

Our Northern California reservoirs are key to building up our water supply as these are the largest and provide water for the most people and land.

El Nino Rain_2

So What About Us In Southern California?

2015_MonthlyPrecip

We got our first heavy rain last week and there was quite a bit of burn scar flooding and several mud slides. We are close to reaching our monthly average halfway through the month.

No two El Ninos are the same. In 1983, most of the heavy rain and flooding in Los Angeles came in the month of March. In 1998, six storms brought more than 13 inches of rain in February. On average, we get six storms throughout an entire year.

3Vert_ENSO

If you are wondering how much rain we need to erase the deficit in Southern California, we’ve got a long way to go.

2015_DroughtDeficit

Our El Nino will end up being the strongest or second strongest on record, and comparing the top five the range in rain amounts is between 20″ and 30″. So, unless we break a record, we’ll still have a deficit, but of course the more rain we get the better.

2015_Significant El Ninos

As of mid January our current El Nino is tied with 1997/98 and peaking right now.

 

El Nino Index

 

 

El Niño strengthening and what that means for us in Southern California
July 7, 2015

2015_El Nino Strength

The latest El Niño forecast is in and it is looking more and more likely that we are in for a very strong El Niño through the winter of 2015-16.  There is even a 60% chance that we could experience the strongest El Niño in modern times.  So what does this mean for California and especially our drought?  Keep reading and I’ll try and answer this question.

ElNino_Forecast

The above image is the latest forecast for El Niño.  This shows the different models and what they are projecting.  As you can see, almost all of them are forecasting a strong El Niño with some even above the record El Niño of 1997.

2015_El Nino Rainfall

Of course the big question is: Will we get enough rain in the winter to get out of our horrific drought in California or at least make a big dent in it?  One of the biggest misconceptions when it comes to El Niño is it ALWAYS brings rain.  There is the belief that every El Niño will be like 1997-98 or 1983-83 when downtown Los Angeles received 30 plus inches of rain during the water year.  The atmosphere is not that simple.  Some El Niño seasons have been dry, some wet, and others are somewhere around average.  Going back through 1950, we have seen 22 seasons with an El Niño, 12 had above-average rainfall and 10 were below-average.  This data shows a slight trend toward wet winters, but you can see it is far from a guarantee.  This is the part of El Niño that is impossible to predict.

2015_Significant El Ninos

However, the one strong correlation to getting the rain we need is if we get a significantly strong El Niño.  Check out the above graph and how all significant years brought well above average rain amounts.  If El Niño forecast continues in this direction I do think we will receive a tremendous amount of rain this upcoming winter.  To get out of our drought in California we need widespread amounts of two feet just to get back to normal.  If we get that in one season we’ll get flooding and mud slides.  We also need more than just rain.  We need our northern California mountains to get snow.  A concern I have is, if the temperatures are too warm, we’ll get a lot of rain but no snow.  The snow in the Northern Sierras is our year-round water supply for families and farmers.

ElNino_Compare

Check out how our July water temperatures compare to the El Niño of 1997.  That year was warmer and more widespread from the waters of South America, but the two are fairly close.  An interesting note: Hurricane Dolores was able to keep its circulation as it moved closer to southern California because the warmer waters in North America kept it from completely dying.  It was Dolores, along with a monsoonal flow, that brought about record-setting rain July 18th and 19th.

2015_El Nino Hurricane

In any El Niño season we see an increase in Pacific hurricane activity and a decrease in the Atlantic.

2015_Drought Monitor

Even with the record-setting July rain, there is no recognizable dent in the drought.  We went from 47% exceptional drought to 46%.

2015_El Nino Effects

What is interesting for Los Angeles in particular is we also don’t get as many 90-degree days in the summer.

2015_What Is El Nino

El Niño is a warming of the water off the Pacific coast of South America.  El Niño’s are categorized by their strength, ranging from weak to very strong.  This past winter was a weak El Niño.  No two El Niños are alike.

Special thanks to David Biggar for the graphics and research.

A Wet Start to 2012
February 20, 2012

It’s been 20 years since we’ve started the year this wet.  In 1992 11.57″ of rain fell from January 1st through February 19th.  This year 11.05″ of rain has fallen at Bush Intercontinental, putting us in 6th place for the wettest start to the year. 

   

Other cities in Southeast Texas have also had beneficial heavy rain.

College Station has received 12.08″ of rain so far this year; only 1991 has been wetter with 17.28″.
Hobby Airport has received 12.20″ of rain, putting it in fourth place.
Galveston is out of the top ten in 12th place with 10.27″ of rain to start 2012. 

More rain is possible Wednesday and Thursday and the new United States Drought Monitor comes out Thursday.  It will be interesting to see how much improvement we’ve made since the 14th.  Any bets that parts of Southeast Texas will get out of the drought?

Dust Bowl Fires
September 9, 2011

This question was brought to you by the students at the Continuum Academy & Learning Center in Livingston.  They visited me at the station and presented their research on Texas droughts in the last 100 years.  They explained how the Dust Bowl of the 1930s would not happen today because we learned from our mistakes of taking  land for granted.  They also shared how there were almost no fires during the dust bowl because of the blowing sand.  Sand puts out fires.  With the abuse of the land there also wasn’t a lot of vegetation or grass to burn.      

To view past weather quiz answers click here:

Past Weather Quiz Answers

2011 Hottest Year Ever Recorded
August 21, 2011

We are on track to set the hottest year on record in Houston with an average temperature of 72.6 degrees.  This is rather incredible despite our cold winter.  Interesting that second place is exactly 100 years ago.    In a typical year Houston’s average daily mean temperature is 67.9 degrees. 

Focusing on the month of August, Houston’s average temperature is 82.3 degrees.  However, this August our average is 90.7.  The record was set last year at 87.7 degrees.  Being three degree above our record is almost inconceivable.   

Why Is The Drought This Bad? When Will It End?
August 16, 2011

I get asked this question every day, so with this posting I’ll try to explain why this is happening and what will change it.

A few things to understand: Since Hurricane Ike in September 2008, we’ve been below average in receiving rain. Thus, our drought has been going on for three years, but it got really bad starting in February of this year. Jan. 24, 2011, was the last time we received more than 1 inch of rain (1.94” fell that day.) February through May were extremely dry in southeast Texas, and our state and our drought went into a tail spin.

Monthly Totals:
End of Winter
February: .69″
Spring
March: .78”
April: .11”
May: .33”

Since records have been kept, we’ve never had four-straight months where we were unable to receive even an inch of rain. The drought is more than just high pressure. These four months had some elements that came together and put us in the “perfect storm” of not getting storms. First, there was a ridge of high pressure that kept the organized storms tracking to our north. Second, our spring months brought an inversion to Texas. An inversion is a layer of warmer, stable air in the upper atmosphere that prevents storms from forming. Third, the jet stream was abnormally fast these months. That kept the rain that did form moving, so we couldn’t get prolonged showers. This fast-moving jet stream brought strong winds into the state too fast to bring rain. These were the months of the record-breaking tornado outbreak and floods in the U.S. The perfect conditions for severe weather, but not for us.

By this time the drought was well established and you have to understand this principle: Drought begets drought. Suffering through these unprecedented dry months actually set in motion a drought that can’t be overcome on its own.

When it is dry, there is more evaporation in the atmosphere. More evaporation leads to hotter temperatures. Hotter temperatures make it drier, and with the dry air you get more evaporation. This leads to more drought. It’s a vicious cycle.

Monthly Totals:
June: .92”
July: 2.98” (Normal)
August, so far: .07”

It’s always hot in the summer, but this year is different. The drought has actually brought hotter temperatures. The drought and heat feed off each other. While we did receive a normal amount of rain in July, it didn’t help with the drought or heat. Our rainfall deficit for the last 365 days is about 30” and one average month doesn’t make a dent.

A lot has been made about the high-pressure ridge this summer. Yes, it is a big factor, but most of the winter, spring and summer it wasn’t right on top of us. The high pressure is close enough to bring in sinking air, similar to an inversion, but we’ve had plenty of opportunities to get rain in the last seven months and nothing forms.

There are three drought busters: a hurricane/tropical storm, change of seasons and a change of the weather pattern. A change of season won’t help much because fall fronts won’t bring enough rain. We had plenty of fronts in February, but most brought strong winds and not much rain. A weather pattern change will help, but we’ll need a prolonged wet pattern. It will have to last months. The quick fix is a hurricane or tropical storm. There is no guarantee we get hit this summer, but I’ve never received so many emails of people hoping to get a hurricane. Desperate times call for desperate measures. How long will the drought last? No one knows for certain, but it can last several years. We need to pray for rain.

100 Degrees 8 Days and Counting
August 9, 2011

As of Tuesday morning, we have endured 19 100-degree days in Houston this year.  It’s basically four times our average of five 100-degree days a year, but short of the record set in 1980.

The streak of eight in a row puts us in fourth place of longest 100-degree streaks.  Since Aug. 1 we’ve been either 100, 101 or 102 degrees.  We would need to hit 100 degrees every day this week though Sunday to tie 1980’s record.

Besides the 100-degree temperatures this month, we are now the hottest YEAR on record with an average high of 72.2 degrees.  This ties us with 1911.  After today, we will stand alone on top.

Of course, the drier ground makes it hotter. We are also the driest year on record, 18 inches of rain below normal.  It’s taken two and a half years to get the drought this bad. Unless we get a drought buster, like a tropical system, it will take a long time to dig ourselves out of this hole.

We Desperately Need the Rain
August 8, 2011

Photo by: Shelly Parsley, Lake Houston

This is a bench that usually overlooks water, today it is a sea of weeds.

Photo by: Jim Bunt, Canyon Lake at the Guadalupe River

Usually you can’t see the ladder to get out of the water.

Drought Worsens
August 8, 2011

It’s good Jim got here in 1957. That year ended a seven-year drought and some brutally hot temperatures. Usually, the way we get rain in the summer is from sea breeze thunderstorms that spark up in the afternoon. There have been two problems with that this year. First, the ridge of high pressure has been influencing us by bringing in sinking air. That acts to prevent storms from forming. Second, the drought affects temperatures and rain. We’ve been in a drought since Hurricane Ike hit in September 2008. We’ve been getting drier and drier for two and a half years. The combination of dry soils and high pressure creates a weather pattern that brings less rain and hotter temperatures. Look at the graph below and see just how dry June 2011 was compared to the previous 100 years. The first six months of 2011 were the driest first half of any year on record, and it’s not even close. The only hope is to have a tropical system bring heavy rain because our weather pattern won’t change the rest of the summer.

SE Texas Drought
August 4, 2011

Not only is it dangerously hot, but I don’t have rain in the forecast for the next two weeks.  Tony Tarver sent me these pictures chronicling the water level going down at Lake Houston.

From Tony: “This is how the drought is affecting the water level at Lake Houston. The first picture is my wife kayaking in front of a pier. At this time, the lake water level was near-normal, although already in decline. I shot the second picture June 30 of my wife kayaking in front of the same pier nearly three months later. At this time the entire pier was out of water. Today there is no need for a kayak, as you can see.”

Uncharted Territory – Our Drought
June 14, 2011

  

The honest answer is we don’t know how long the drought is going to last. If we get a slow-moving tropical storm that brings more than 15 inches of rain, it would end this summer. That is unlikely. It could also last 10 years.  There have been two decade-long droughts in Texas the past 100 years.  No one really knows when the drought will end. It’s a lot of speculation.  I can tell you this: Since Hurricane Ike, we’ve been below average with rain. We’ve been in at least a minor drought since 2009, but it started getting really bad in October of 2010 and the last four months have been awful.  To get out of the drought, we’ll need an extended wet pattern that lasts several months, and that won’t happen this summer.  We are in uncharted territory with this drought. I go into the details on this webcast.  Click the image above to watch the webcast, or click here:

http://www.click2houston.com/video/28230621/index.html

 

Your Summer 2011 Forecast
June 10, 2011

I answer Wayne’s question on this webcast.  Click image to view your summer forecast.

Heat and Drought Records
June 9, 2011

Click image to view Thursday’s webcast.

Unprecedented Drought
May 27, 2011

What are you seeing with these rain amounts in this picture is unprecedented.  I’ll explain.  Click image to view webcast. 

Ask Anthony… Water Restrictions
May 10, 2011

Hi Karen,

I don’t make those decisions, but, with the weather pattern unchanged possibly for the next two months, I don’t think we are too far away from seeing the cities in southeast Texas asking residents to conserve. It will probably start voluntary, like what we are seeing in Galveston County. The longer the drought lasts, the more restrictions we’ll see. I grew up in a desert, and almost every summer the city would have DON’T water the lawn days. If the drought was bad enough, the resident could be fined if they watered on what was called a “red” water day. Specifically, the city of Houston has ample water supplies and won’t impose any restrictions in the near future but if this drought continues I would expect to see some sort of restrictions put into place.

Ask Anthony… Cloud Seeding
April 28, 2011

This is an e-mail I received from Ray:

With the drought in Texas being so severe and watching all the moisture laden clouds being drawn to the storms north of this area…  I keep wondering why the government doesn’t consider seeding those clouds.  Seems to me that it would be cheaper than fighting the wild fires and could also reduce the intensity of the storms further north.  If technology can make cloud seeding work now it would truly be a win-win.

Hi Ray,

Good question.  The problem is it wouldn’t be cheaper.  Cloud seeding takes fuel, chemicals and, of course, an airplane.  None of these are cheap on the scale we are talking about.  One plane won’t do the trick, and are we going to ask the government in these cash-strapped times to send out hundreds of planes making hundreds of trips to cover a relatively small area?  Our state is huge — what counties are left out?  Who gets the seeding?  West Texas, where the fires have been the worst, is a dry climate. Seeding may work for a short time, but lower humidity would erase all moisture picked up by the vegetation.  There are also the political impacts.  What if Montgomery County is sprayed and fires break out in in Liberty, Waller and Walker counties? People would start asking if rain was “taken” away from their cities because someone in the government felt Montgomery County was more worthy.  Lastly, there is still some debate out there about if weather cloud seeding really works.  Southeast Texas is a good example of how seeding the clouds may not help.  Our problem isn’t a lack of moisture, it’s the strong inversion over our area.  More moisture won’t break the cap on our atmosphere.  We need low pressure, the jet stream or some other strong lifting mechanism to break the cap. Once that happens, we’ll get rain.

To sum it up, it would cost too much, help too little and there is no guarantee it would bring about the results needed in the areas sprayed. 

100% of Texas is in A Drought
April 22, 2011

 

Click image to view Friday’s webcast.

Why We’ve Been Dry (Part 3) & The Tropics
April 21, 2011

On this webcast I show the weather patterns the last six months and explain why the fires have been so severe in Texas.  And the tropics coming alive in April?  It’s happened before.  Click image to view Thursday’s webcsat.

Drought Worsening
April 18, 2011

 

Click image to view Monday’s webcast.

Why We’ve Been So Dry (Part 2)
April 14, 2011

Yesterday on this blog I shared how a strong upper level flow is moving storms in and out of Texas so fast that we can’t receive more than just a passing shower.  Today I discuss how a strong inversion is preventing storms from forming.  This inversion has been in place since October, and we need a strong low pressure area or dry line to break it.  Click image to view Thursday’s webcast:   

Latest On Our Drought
March 21, 2011

 

Click image to view Monday’s webcast.

Drought Moving West
October 25, 2010

 

Click image to view Monday’s webcast:

Are We in a Drought?
October 13, 2010

 

Click image to view Wednesday’s webcast: