Friday, May 30, 2014

Late May update (May 30, 2014)

NOTE:   It would also be helpful to read the previous posts on this blog if you have not done so before now.

For official long range forecasts, go to The Climate Prediction Center.

(Click on images for a larger version)

Since the last posting on May 9, 2014, there have finally been small signs of what I've been expecting. Although not everyone received precipitation, or at least a substantial amount, there were definitely areas that received copious amounts of rainfall.

Unfortunately, there are still many locations that have not received much rain.  Therefore, the drought continues and in fact has intensified as we get deeper into the warm season.  But, areas of west Texas and eastern New Mexico did receive substantial rains and that, hopefully, will help it to green up which will have an impact of the high plains of Kansas later this summer.

Picking just one site, in the case Dodge City, shows how the deficit of precipitation keeps growing.  Keep in mind that parts of Ford County and Dodge City received very heavy rainfall on Mothers Day (May 11).

Without that rainfall the growing deficit at Dodge would be so much greater!  The graph above shows the accumulated precipitation for Water Year 2014, or from October 1, 2013 through the current date.

The next graph illustrates just how bad it is getting (and it's a lot worse at other locations).  This graph shows the accumulated precipitation since October 1, 2010 through the current date (or WY 10 through WY14).

So is it going to get better?  If you surf the 'net' there are varying opinions.  Some say the drought will expand and intensify throughout the summer and into the fall.  Personally, I've been expecting a gradual change to a wetter regime and so far that is the trend (although it would be hard pressed to see at a lot of the very dry locations).

However, one of the biggest disappointments of this trend is the lack of widespread heavy rainfall that SHOULD have occurred this past 10 days of May.  An upper low formed over northern California on May 19th and it has taken 10 full days to reach northern Louisiana.  The track and position should have brought a copious amount of rainfall to a very large part of the central and southern Plains.  Indeed there were many locations that did receive a bunch of rain, and some that had excessive rainfall.  But the rest of us? Puzzling.

This pattern of slow moving systems will likely repeat several times until late summer.  At the same time there should be an above normal amount of frontal passages into the U.S. and the thought is that many of these will make it as far as the central plains.  Given that scenario, I'm optimistic  that above normal rainfall will result across much of the high plains as moisture is transported westward into the higher terrain to the west.  The "killer" to this may be the upper level ridge that should set up somewhere across the Texas.  Will it be too strong and cap the atmosphere?  That is a possibility which would limit the chances for periodic convective systems, and therefore bring rainfall totals back to normal or even a little below normal.

One of the long range computer models (CFSv2) has been very persistent and consistent in forecasting at least normal if not way above normal rainfall into July.  This model generates an outlook based on current conditions and is run several times after changing initial conditions slightly.

The graphic below shows the wettest run of the CFSv2 based on data from upper air soundings on May 29. As you can see, it is VERY wet!    The second map shows the average of all the runs based on the same data.

Again, this computer model has been very, very consistent in this type of output.

Finally, you may have heard about an El Nino developing and even developing into a super Nino.  Hold on, there is more to the story.  So far it has been a major struggle for the event to even start.   I don't like the trend.

The green trend on the graph above should be dropping to well below zero.  So far, it's not!  There are very warm waters just north of Australia and this may prevent a coupling of the oceanic warm waters in the western Pacific basin.  What that means that IF an El Nino develops this fall and winter, it may not be that strong.  That could have impacts on the western U.S. and southern states, which in turn would impact weather in Kansas.   We need to root for a decent El Nino as all major recorded droughts in the plains states have been broken by such an event.  Computer models still indicate that one will develop later in the year and into next - the stronger the better I believe.

I'll update again after June 15th.

Friday, May 9, 2014

Latest Update on the Sring & Summer Outlook (May 9, 2014)

Before going further, make sure you review the original post made on April 15, 2014...located at Spring & Summer Outlook.

It's been a very disappointing weather regime so far this spring.  Under ideal and even "normal" spring conditions, these weather systems that have brought "weather" to parts of Texas, Oklahoma, Missouri and points east (and even far eastern KS) would have brought many rounds of spring storms to all of Kansas.  As it stands, it appears the flow aloft has just been too strong and too far north and with bad timing.  Boundary layer moisture has not had a chance to move far enough west to be lifted by these systems.  Early in the Spring the moisture was even too limited across Texas and the deep south due to persistent cold fronts during the winter.

Now that early May has arrived, at least the gulf moisture has been more robust and farther west and north.  What this means is that with time, moisture will be utilized by the weather systems moving in from the west so that precipitation opportunities will be increasing.   Granted it is likely too late for much of the winter wheat, especially in the hardest hit areas of the drought.  All the very long range forecast models (U.S. and abroad) have been persistently indicating above normal precipitation for May.  It is bothersome that  scenario has not been realized yet.  Each passing day that nothing materializes leads to less and less confidence.  But at least the cycle is's just a matter of time!

Not only has the dryness increased across much of the area bringing the demise to much of the wheat crop, but now we'll have to worry about another freeze!  As has been expected since late winter, this next cold outbreak is right on time.  This next week (May 12-17) will see low temperatures well into the 30s and with any clearing and decreasing winds, there is a chance the mercury will fall into the upper 20s across at least far northwest Kansas.

Update on the drought.  The latest is the drought assessment for plains updated on April 29, 2014.

...and for Kansas...

Speaking of the optimistic long range models.  The  Climate Forecast System Version 2 (CFSv2) from NOAA has the following forecast (just one model run) for the period of May into early June.  Needless to say...WET!

If this verified, almost the entire corn belt would be very wet!  And, wet across most of Kansas!  Again, these models have been very persistent with these wet outlooks but it just hasn't started yet.  I'm still staying optimistic that things will turn around.

Finally, as I pointed out in the mid April post, all major droughts have been "busted" by developing El Nino conditions.  An El Nino has been expected to develop, but so far it has been a VERY slow process with some thought that it might not happen!  The following is an updated plot from April of the SOI (Southern Oscillation Index).  We want to see negative values!  It is slowly trending that way, at least (look at the 90 day or green line).

The outlook is for the El Nino to continue to develop, and with high confidence of that happening.  The big question is just how strong it might get and for how long.  I wouldn't be too suprised to see just a weak/moderate Nino and wouldn't persist too long given the state of the atmosphere and climate.  But at least it would increase the opportunity for above normal precipitation later in the summer and into the winter and next spring/summer.

I hope to update this again before the end of May.