Category Archives: organic forecasting

42nd Climate Prediction Center Diagnostic Workshop Abstract Submission

On Friday the team submitted an abstract to the #42CPCDW with the title…

 

Utilizing the Daily Southern Oscillation Index Changes to Determine Severe Weather Potential On A Subseasonal Scale

 

We are coming up with amazing results and can’t wait for the opportunity to bring them forward.

Research and Forecast Rodeo Updates

Hello everyone,

I’ve been digging deep into multiple command line programs that we utilize for looking at various netCDF files along with some python coding to further my research into the intraseasonal oscillation and how it affects the #organicforecasting methodology.

Below you will see how the team is doing utilizing the #RRWT for a year long forecast rodeo.

Here you can see how we are performing against the top teams.  Keep in mind that this is among 188 of them!

The current Southern Oscillation Index research is going well and we have a few abstracts ready for the CPCDW in Norman, OK this October and the AMS18 in January!

Forecast Rodeo Comparisons

Hello everyone!

The team received this email today regarding the Forecast Rodeo

I am looking forward to the ‘official’ scores mid-month, but in the meantime, let’s look at how we fared.

Here are the forecast that we provided the rodeo with on 4/04/17 for the period of 4/18-5/1.

Accumulated Precipitation in millimeters

Average Temperature in Celsius

A few different looks at the results…

Precipitation in inches

Temperature in Fahrenheit

Now…since the Western Region Climate Center doesn’t extend into the Plains, I’ve included the complete US maps below. Otherwise, I’d have to include 2 of each from the High Plains & Southern regions.

Due to the difference in data, mm vs in & (C) vs (F), note the patterns instead…unless you are fine with converting each.

The evaluation criteria information for said rodeo is listed below…

Evaluation criteria

Forecast skill will be evaluated for temperature and precipitation separately since the drivers responsible for prediction of these variables are different and the subsequent skill level is also expected to be different. Moreover, the 15-28 day and 29-42 day periods will be evaluated individually for similar reasons. Winning forecasts must outperform CFSv2 and damped persistence forecasts (see definitions below). Specifically, skill will be evaluated individually for temperature and precipitation for weeks 3-4 and weeks 5-6 as the highest skill over the competition domain, averaged over the entire competition time period. To be prize eligible, Solvers must also demonstrate historical skill of statistical significance that is equal to or greater than that of the CFSv2 through submission of a hind-cast analysis described below.

So, with the above in mind, let’s look at the CPC Weeks 3&4 forecast. Yes, I’m familiar that it’s not the CFS Week 3&4, but I couldn’t grab the archived forecast.

Precipitation Anomaly Forecast

Temperature Anomaly Forecast

 

The resulting anomalies…

February Verification

Hello everyone! I know, I know…”Joe, you are quite a bit late on the February verification post!” There were so many different routes that I couldn’t decide to take on this that it left me confounded.

One thing that I’d like to touch base on was the 3 day ROC scores for the Northeast during February. Astonishingly good would be the best way of describing it!

 As you can see above, not only did the 3 day ROC of the BSR nail the pattern overall during February, but it literally had a 1:1 correlation on multiple days!

The 7 day pattern correlation of the ROC shows the high correlation even better with score verification.

The first 5 days of the month showed this as it pertained to the BSR 500mb map.

 As you can see above, the Western ridge/Eastern trough was foretold. The trough was focused over Quebec, extending into most of the Eastern US, and the ridge was focused over the Intermountain West.

The above graphic from the ESRL daily composite site, with a focused point of the US, shows the ridge verified SE of the BSR while the trough apex was split between Newfoundland and James Bay. The ridge extending to the SE coast nullified the minimal BSR below normal look South of the Mason-Dixon line.

The next event I will bring up is the February 7th, 2017 severe weather that hit the Gulf Coast. The idea which the BSR started to paint was one which had a system develop over the lee of the Rockies and move East affecting the gulf region.

The first “official” hint on the organicforecasting.com BSR section was January 16th, 2017 with the 96hr OPC forecast overlay.

 While these overlays were produced on January 21st, 2017 based on 500mb analysis.

Almost immediately afterwards, we saw the potential for a strong storm to hit the Northeast via the next system based on the 96hr OPC forecast overlays starting on the 18th of January, 2017.

These maps are based on 500mb analysis once again.

Compare the maps for February 10th to what the Weather Prediction Center had for Days 5 & 7 forecast of February 9th on the left side of the next two pictures!

 Day 7 Forecast vs Verification

Day 5 Forecast vs Verification

On the Accuweather.com forums we have “adopted” a naming strategy to storms which the BSR nails…”Dark Knight Blizzard” as my nickname is the “Dark Knight” dating back to the January 20th, 2016 storm. This is the forecast thread, while here is the OBS thread for the DKBIII storm.

I will reference something that was brought up in the weatherboy.com article dated February 12th, 2017.

This is a warm pattern upcoming for much of the U.S., especially east of the Rockies. In the 10 day period ending around the 22nd of this month, many areas of the country will be 10 degrees above normal with some as high as 20 degrees above normal. Though New England will be the slowest to warm, after the current blizzard departs, temperatures will soar even there to well above normal readings about a week from now. While they warm slowly in New England, temperatures in the Midwest, Great Lakes and South will be well above normal for much of this upcoming week.

“A strong area of high pressure over the North Pacific near the Gulf of Alaska retrograded, meaning it headed west, instead of the normal east that most weather systems take (in late January) and this teleconnected to a ridge of high pressure off the Southeast coast heading west and dominating the eastern US,” explains Renken.  This type of weather pattern encourages a strong west to east flow across the Lower Forty Eight  and will combine with the much stronger than normal Pacific jetstream to allow warmth to dominate.

Below you can see the Des Moines, IA data for the period of February 1st-22nd. I placed the 10 day period from the 12th-22nd in red squares.

Even though I didn’t see the departures get larger than 20° above normal, the pattern was foreseen and warned about. I suspect that the raging Pacific jet that I spoke about added extra moxie to the pattern.

While the pattern indicates a warm stretch of weather, a change is also likely around the 20th of the month. “This very well could be another severe weather outbreak with the Southeast with the Gulf Coast states being the area seeing the greatest threat for severe weather,” Mr. Renken stressed.

Even though the outbreak didn’t come true due to mesoscale features not lining up, the potential was there and foretold.

Here are the reports from the 19th.

The SPC outlooks for the remaining days.

BSR map created on February 3rd, 2017. Note the ULL over West Texas, the corresponding ridge over the Deep South, another ULL off the SE coast and the Mid-Atl.

The West Texas ULL hasn’t closed off yet in the OBS, but the ridge is created ahead, ULL between Bermuda and the Bahama’s, and the last ULL over Nova Scotia.

A look at the BSR ESRL generated map for the 18th-22nd.

This is the corresponding OBS at 500mb.

This storm will be followed by a change to more normal temperatures.  Mr. Renken explained, “The stronger than normal jetstream slamming into California has been the overwhelming meteorological factor in our mild winter so far. And there is no sign of this factor going away. Plus Canada has been running way above normal temperature-wise. Combining these and other factors, I don’t think a pattern of sustained cold in the East will exist.”  After the stormy period that’ll set-up around February 20-22  and into March, the BSR indicates a volatile back and forth temperature pattern with some cold snaps but the cold is generally muted.

The BSR had this for the last 4 days of February.

Here are the last 4 days of February…

 Boston, MA data showing the cold was “muted” as predicted. That being said, going from 25° above normal to 7° above normal is a nice cold front that I’m sure those in the region were happy to see.

These are the 3 day ROC charts for the Mountain and Central regions.

The Mountain 3 day ROC had the pattern, but not the magnitude during the same period.

While the Central 3 day ROC was off by 3 days in the recovery.

So, overall, I’d say that the BSR did quite well during the month of February!

Severe Weather Calls

Hello everyone!

In the last article, March 18th, for weatherboy, I was quoted for a few dates of severe weather to ramp up.

According to the BSR, the days with the greatest chance of severe weather would be around the 23rd and 24th of March, the 2nd through 4th of April, and then again later in April, around the 10th through 12th.

Here are the archived BSR maps provided on the organicforecasting.com.

 March 23rd, 2017

 Forecast on March 6th, 2017

March 24th, 2017

Forecast on March 7th, 2017

April 2nd, 2017

Forecast on March 16th, 2017

April 3rd, 2017

Forecast on March 17th, 2017

April 4th, 2017

Forecast on March 18th, 2017

April 5th, 2017

Forecast on March 18th, 2017

April 6th, 2017

Forecast on March 19th, 2017

April 10th, 2017

Forecast on March 24th, 2017

April 11th, 2017

Forecast on March 25th, 2017

 

Let’s take a look at those dates via the Storm Prediction Center’s report page. These will all be filtered reports to take out those which were duplicates.

March 23rd, 2017

March 24th, 2017

April 2nd, 2017

April 3rd, 2017

April 4th, 2017

April 5th, 2017

April 6th, 2017

April 10th, 2017 Day 1 Outlook

April 10th, 2017 Day 2 Outlook for 4/11-4/12

 

What Happened With The BSR?!

Hello everyone! I’ve decided to follow up on an article that I was interviewed for with The Weatherboy.

First, let’s look at the outlooks from an earlier interview on February 12th

After the stormy period that’ll set-up around February 20-22  and into March, the BSR indicates a volatile back and forth temperature pattern with some cold snaps but the cold is generally muted.

Here are the stats for Bangor, ME in February and the first part of March. Bangor, ME is our correlation point with Kodiak Island, AK.

As you can see, the volatile pattern is there.  The cold snaps of late February didn’t materialize because of the Pacific jet coming back to life per this graphic. So my comment of them being “muted” was spot on for the later part of February.

The low pressure well of the West Coast acts as a catalyst to increase the speed of the jet once it turns zonal over the CONUS.

Another method that we utilize in the BSR is our 3 Day ROC, or Rate of Change. The orange line designates our correlation on Kodiak Island, while the green designation is Bangor, ME.

Note how the 3 day ROC basically nailed the pattern from 2/12/17-3/10/17. This can be confirmed by looking at our 3 day ROC pR option below.

The above graphics were brought up in the Weatherboy article

We keep a detailed record of what the BSR’s repeating pattern, its so-called ‘lag’, is every day.

One thing I’d like to bring up is how the BSR did show a storm in the MidAtl and Northeast on March 13th as seen below.

A dissipating low pressure just South of Cape Hatteras, NC with two shortwaves to it’s West.  One stretching in the Mid-Mississippi River Valley and the other from the Ohio Valley to Cuba.  It’s obvious that these two shortwaves ‘phased’ and gave us…

Finally…there is a forecast method that is utilized by multiple NWS offices which uses Hovmoller graphics. This “in-house” method stated that the severe weather threat for the Plains and Upper Midwest actually merged with a long range “frequency”, or “signal”, to create the above storm off the Northeast coast.

Finally, be careful of anyone on “wxtwitter” or various Facebook groups that claimed they foretold a big storm coming well in advance of 20 days! Them saying that the Mid-Atlantic and Northeast stood a chance for snow is a huge difference than calling for what was on the table!

Climate Prediction Center 8-14 Day Looks Familiar

Hey everyone!

Here is the CPC 8-14 day temperature outlook issued last night for the period of March 4th-10th.

Here is what the BSR was showing on February 20th.

That being said, the BSR ESRL maps have a lag of developed and we can see the pattern 6 days earlier as the surface and 500mb maps are produced.

The BSR’s Use Across The Lower 48

One of the meteorologist who utilizes the #BSR is Jeremy Nelson, formally of WISN in Milwaukee and now at WJCL in Savannah, GA.

Recently, Jeremy posted a blog regarding the daily record amount of rain that Savannah received…1.88″ to be exact.

Here is what the #BSR was showing…

Note the multiple low pressure systems along the Gulf Coast and a strengthening low in the Trinidad, CO region.

Here is the observed surface map for 12z 21FEB17..

and the 500mb map for the same date/time…

The OBS surface map above has multiple low pressure’s along the Gulf Coast that are occluded.

First mention of the end of February was back on January 29th.

Jeremy followed up regarding the end of the month for a strong system to impact the SE on January 9th.

A few tweets about a warmup around the 11th and 12th of March…

and another warm up immediately following a chance of rain…

We are looking forward to his verification and #bsr intro blog post for those in Savannah, GA!