Wednesday, April 25, 2018

Wednesday Wheelhouse: IATA and ICAO Airport Codes; A Freakishly Circular Florida Natural Lake As Seen from Above; and Recent Rainfall by the Numbers for KDCA, KBWI, KIAD, & KATL

View from Delta flight 2439 from Daytona Beach Int'l Airport (DAB) to Hartsfield-Jackson Int'l Airport (ATL) looking to the west during initial descent (probably around 25,000 feet) somewhere over southwestern or western Georgia, 7:01PM EDT, April 23, 2018.


We had followed a more westerly route than usual to avoid thunderstorms passing through the Atlanta area and went on a route that took us just north of Tallahassee. I was seated on the left side of the jet and saw it below, including the main airport (TLH!) and a stadium I ascertained later was FSU's Doak Campbell Stadium.

Ascending from DAB above the Daytona Beach coastline, Delta flight 2439, 6:14PM April 23, 2018.


About 10 minutes earlier, the jet also passed almost directly over the weirdly nearly perfectly circular Kingsley Lake located in Clay County, Florida. (I figured out last night via Google aerial view that this is what I had seen.)

The naturally nearly perfectly circular Kingsley Lake, Florida; source image here; apparently, the lake is the result of a (very large) sinkhole.

The picture of the lake directly above was taken from several feet up, whereas I saw it from about 30,000 feet almost directly overhead. There was no mistaking Kingsley Lake's incredibly circular shape, nor the network of roads around it.

Wikipedia (black and white) high-altitude image of Kingsley Lake from directly overhead.


IATA versus ICAO Airport Codes

Oh, yes, in the unlikely event you were wondering ...

The three-letter airport abbreviations are International Air Transport Association (IATA) codes while the four letter ones are International Civil Aviation Organization (ICAO) codes with the ICAO also used for weather/climate stations including those in the Automated Surface Observing Systems (ASOS) network run jointly by the NWS, FAA, and DoD. For many larger U.S. airports, the two are the same except for the ICAO's "K" addition.

Thus, ATL = Hartsfield-Jackson International Airport while KATL (as I am using it) is the ASOS station at ATL. Ditto DCA/KDCA; BWI/KBWI; and IAD/KIAD, not to mention DAB/KDAB.


OK, now that we've gotten that out of the way ...

This is not my planned entry recapping my combo Flagler Beach and Daytona Beach visit to see my dad and vacation with my mom. That's going to take a bit of time for me to compose -- although I promise it isn't going to take 8 months in the manner of my South Carolina eclipse trip entry.

Sterling (LWX) NWS radar in standard base mode reflectivity looped 12:02 - 12:39AM EDT April 25, 2018.


Rather, this entry is just to catch up on a few weather-related items -- specifically, regional rainfall / precipitation amounts. It includes some radar and weather advisory product images from early last week that I had intended to post in a previous entry but never got around to doing.

Sterling (LWX) NWS radar in standard base mode reflectivity looped 1:16 - 1:55AM EDT April 16, 2018.


It is an overcast, misty, mild day with scattered light rain showers. Air temps are in the 62F to 65F range and the dew point in the 55F to 60F range at the 2PM hour in D.C. and immediate environs.

NECONUS composite radar mosaic looped 0318 - 0428UTC April 16, 2018.


Rainfall yesterday into this afternoon (through 3PM) were decent (even if National Airport brought up / is the rear) and included the following amounts:

KDMH: 1.91 inches
KIAD: 1.04 inches
KBWI: 1.01 inches
KDCA: 0.78 inches

Screw National Airport.

This rainfall was in addition to a decent amount on April 15th - 16th that included the following amounts:

KDMH: 2.24 inches
KDCA: 2.01 inches
KBWI: 1.54 inches
KIAD: 1.47 inches

There is another chance of light-to-moderate rainfall on Friday, and if that pans out, we should end up about normal for the entire month. Year-to-date (YTD) through yesterday includes the following (with normal YTD in parentheses):

KDCA: 10.20 inches or minus 1.15 inches (11.35 inches)

KBWI: 10.67 inches or minus 1.74 inches (12.41 inches)

KIAD: 10.24 inches or minus 1.33 inches (11.57 inches)

KDMH: 11.62 inches or minus 0.37 inches (11.99 inches) [KDMH average and departures are based upon only a partial climate period.]

This follows months of drier-than-normal weather with the full calendar years of 2016 and 2017 running below normal. In fact, in that time, KDCA was 67.30 inches or 12.18 inches / 15.32 percent below the two-year normal of 79.48 inches.

Baltimore / Washington NWS Forecast Office ("Sterling" or "LWX") county warning area (CWA) radar-estimated rainfall totals for the period 8PM EDT April 14 through 8AM EDT April 16, 2018.


KBWI wasn't down by nearly as much: 78.80 inches versus the two-year normal of 83.76 inches or 4.96 inches / 5.92 percent. (This also follows a wet 2015 with 51.16 inches.) KIAD was below normal for three consecutive calendar years 2015 - 2017: 115.37 inches versus the normal of 124.62 inches or 9.25 inches / 7.42 percent.

Data source linked from here ("monthly precipitation" links).

LWX CWA weather advisory products as of 10:59AM EDT April 16, 2018.


I'd also like to note how impressive was the rainfall in Atlanta on Monday as my mom and I were traveling through Hartsfield-Jackson, and by impressive, I mean, monsoon-like.

It caused a nearly 90-minute delay and a rainy takeoff into a dark and stormy Georgia night. As seen on ascent, the storms produced stunningly awesome (and a tad scary) lightning illuminations through vast vertical expanses of opaque clouds.

Above the storms, in a starry eternity, a waxing just-past-first quarter Moon washed down a ghostly white light upon this boiling, spreading, twisting army of ethereal giants.

Just enough light from the human world below made it through one or two areas of this cloudy cavalry to create brighter patches in an otherwise sea of ashen gray opacity.

Atlanta / Peachtree City NWS Forecast Office ("FFC") infographic for heavy rainfall for the 48-hour period ending early April 24, 2018.


Truthfully, I was a bit surprised that jets take off in such weather but I suppose the limiting factors are wind shear and intense cloud-to-ground lightning. "CTG" lightning apparently comes into play more if a jet is refueling (something about a five-mile area).

Officially, KATL picked up 4.16 inches on April 23rd, a daily record that easily broke a very old, pre-airport record of 2.40 inches set in 1883. It also vaulted KATL from a small YTD deficit on the 21st (minus 0.31 inches) to a surplus on the 23rd of 4.19 inches. (Of note, bout 2.3 inches of this fell while I was waiting at the airport.)

I tried to find at list of the top-10 wettest days at KATL but could not. Instead, I found this tweet from local WSB-TV weatherman Brad Nitz who related that the 4.16 inches was the 9th wettest single day total (and well behind Atlanta's official all-time wettest single calendar day amount of 7.36 inches set in the pre-airport period on March 29, 1886).

Here is a screenshot of the tweet:

WSB-TV meteorologist Brad Nitz tweet on Atlanta (KATL) rainfall for April 23, 2018.


The two-day (April 22nd-23rd) total for KATL was 4.73 inches (with another 0.02 inches yesterday) and widespread across central and northern Georgia were amounts in the 2 to 6 inch range.

Speaking of the KATL weather station, I believe this is an image of it located off one of the east-west runways on the south side of this ginormous airport:

The Hartsfield-Jackson Int'l Airport ASOS station (?) as seen from one of the network of runways and taxiways, 7:27PM April 23, 2018.

It is a very blurry picture with my crap flip-open cellphone camera but I think this is the ASOS. (Of note, snow boards for measuring snowfall are often kept elsewhere for airport-based ASOS stations. KATL gets enough snow that there is almost certainly a regular snowboard.)


OK, I'm going to wrap up this entry. Tonight is a non-gym night so I'll probably stop at one of my usual pair of spots. I'll also try to post another entry late tonight, but no guarantee on that. As I will explain in a subsequent entry, blogging will be light next week.

Now there's a real love and an honest love for a real, honest man and truly great leader.

Sorry, I just threw up a little bit in the back of my throat. Excuse me, I need a Seltzer water. Preferably with some vodka mixed in.


No comments: