Thursday, March 26, 2015

Picture Perfect Weather Days

After all the excitement of the last post (Dreary Weather), I decided to turn the tables a little bit. This time I am mapping the number of "Picture Perfect Weather" days per year. What exactly is a Picture Perfect Weather day? You know, it's one of those days where the people on the local news say that it is a Chamber of Commerce type of day. In my opinion, it is the kind of day that local civic leaders wish for when distinguished visitors come in from out of town.

The Dreary Weather post from a few days ago depicted a composite (unitless) index. The reason for this is because it is otherwise impossible to mix annual totals with daily totals. For this new map, I am only using daily data. Therefore, the results are presented as days per year.

Criteria:

We have to pick some sort of criteria to quantify this and no matter what the criteria are, there will be an argument for and against all of the inclusion guidelines. Oh well. It's my blog and I get to make the decisions!

There are three criteria that define a Picture Perfect Weather day in this study:

1) No measurable precipitation – most readers are probably comfortable with excluding days where precipitation is measured.

2) High temperature between 60°F and 80°F – this one will generate the most angst. In most instances, this is a temperate range that does not require someone to wear a jacket, nor is not overly hot. Again, completely subjective.

3) Average daily cloud coverage is 30% of less – a day with no rain and a temperature of 70°F might be overcast and gray and would therefore not fit the ideal description; therefore, I decided to exclude days that were more than 30% overcast. Perhaps 40% or 50% would be a more reasonable number, but I digress.

Methodology:

Since this study uses daily climate data from the Global Historical Climatology Network (GHCN) database, I only pulled out data observations that included cloud cover, precipitation, and temperature. This massively reduces the number of stations available to use. However, it has the advantage of not requiring interpolation (as the Dreary Index did). Plus, it allows us to have a more meaningful measure; i.e., days per year.

For inclusion in this data analysis, all observations between 1965 and 1966 in the GHCN database were evaluated and those records matching the criteria in the previous paragraph were grabbed. The 1965 to 1996 time period was utilized because that is when manual cloud coverage estimates were made prior to the nationwide implementation of ASOS.

Results:

The results of the analysis are cartographically shown in the map at the top of this blog post. Not surprisingly, the sweet spot for precipitation, cloudiness, and temperature is in California and the desert southwest. From a timing perspective, the days in Arizona and Nevada are primarily in the winter. In much of the central and eastern U.S., Picture Perfect Weather days are in the spring and fall seasons. Unfortunately, my home state of Alaska did not fare too well. Too much cloud cover and low temperatures doomed the 49th state. Quite surprisingly, Hawai'i, the emblem of nice weather, fared very poorly too. Cities in Hawaii had a difficult time making the cloudiness threshold and most of the high temperatures exceeded 80°F. So, for Hawai'i, this study produced dubious results.


List of Cities:

Instead of listing all 265 stations, I pulled out the ones that represent cities of 250,000 or more people plus a few additional ones. In a few cases, a city with 250,000 people did not have sufficient data for inclusion.



CityDays
Los Angeles115.1
San Francisco111.5
Oakland103.5
San Diego90.0
Flagstaff84.7
Yuma78.0
El Paso74.3
Tucson70.3
Sacramento64.7
Las Vegas64.1
Phoenix63.5
Midland-Odessa62.0
Bakersfield58.9
Albuquerque58.1
Lubbock58.0
Amarillo56.7
Fresno55.4
Stockton54.5
Daytona Beach48.4
Colorado Springs47.4
Charleston (SC)46.0
Dallas-Ft. Worth45.5
Oklahoma City44.9
Atlanta44.8
Jacksonville44.4
Key West43.2
Charlotte42.8
Tampa42.6
Tulsa42.6
Austin42.3
Baton Rouge42.3
New Orleans40.9
Raleigh40.9
San Antonio39.9
Denver39.8
Kansas City39.7
Memphis39.3
Wichita39.0
Little Rock38.3
Corpus Christi38.1
Houston37.0
New York36.9
Nashville35.8
Miami35.2
Orlando34.4
Des Moines34.3
Baltimore33.6
St Louis32.5
Omaha32.1
Seattle32.1
Salt Lake City31.9
Lexington31.8
Milwaukee31.8
Washington DC31.7
Philadelphia31.6
Chicago31.1
Boston30.6
Cincinnati30.3
Louisville30.2
Newark30.0
Columbus (OH)29.3
Detroit29.0
Minneapolis-St. Paul28.9
Ft. Wayne28.5
Indianapolis28.4
Portland28.3
Toledo27.6
Pittsburgh26.5
Cleveland26.1
Brownsville26.0
Billings25.7
Syracuse25.3
Buffalo24.4
Albany (NY)23.8
Charleston (WV)23.6
Juneau13.0
Anchorage11.2
Fairbanks10.7
Honolulu9.8
Hilo4.0
Barrow0.8

8 comments:

  1. Is there a place you do provide the data on all 265? For instance, I'm from Boise, ID, and I'm curious where it stacks up exactly, rather than via the generalized image (which is indicated with a red dot). I'd like to look at a number of them beyond just Boise, too... if possible. Thanks.

    ReplyDelete
    Replies
    1. Alright, you asked for it.

      Station --> days per year

      Point Mugu:115.4
      Los Angeles :115.1
      San Francisco:111.5
      Moffett:109.8
      Oakland:103.5
      Alameda:101.2
      San Diego:90.0
      Flagstaff:84.7
      North Island:79.6
      Long Beach:78.7
      Yuma:78.0
      Roswell:75.1
      El Paso:74.3
      El Toro:73.2
      Tucson :70.3
      Sacramento:64.7
      Las Vegas:64.1
      Winslow:63.6
      Phoenix:63.5
      Desert Rock:62.7
      Midland:62.0
      Bakersfield:58.9
      Albuquerque:58.1
      Lubbock:58.0
      Amarillo:56.7
      Fresno:55.4
      Abilene:55.4
      San Angelo:54.7
      Stockton:54.5
      Mayport:52.4
      Lemoore:51.0
      Red Bluff:50.8
      Ely:49.4
      Greer:49.0
      Daytona:48.4
      Wichita Falls :48.0
      Reno:48.0
      Athens:48.0
      Del Rio:47.8
      Colorado Springs :47.4
      Pensacola:47.2
      Beaufort:47.1
      Savannah:46.8
      Augusta:46.6
      Columbus Metro:46.5
      Wilmington:46.4
      Charleston:46.0
      DFW:45.5
      Pueblo:45.5
      Meridian:45.3
      Macon:45.2
      Cape Hatteras:45.0
      Ok. City:44.9
      Atlanta:44.8
      Columbia:44.6
      Alexandria:44.5
      Tallahassee:44.3
      Jacksonville:44.3
      Goodland:43.8
      Mobile:43.3
      Key West:43.2
      Asheville:43.0
      Waco:43.0
      Cherry Point:42.9
      Charlotte Douglas:42.8
      Montgomery:42.8
      Whiting:42.8
      New River:42.7
      Tampa:42.6
      Tulsa:42.6
      Austin:42.3
      Baton Rouge:42.3
      Dodge City:42.0
      Shreveport:41.8
      Ft Smith:41.5
      New Orleans:40.9
      Raleigh:40.9
      Meridian:40.9
      Tupelo:40.9
      Lake Charles:40.5
      Jackson:40.5
      Whidbey Is.:40.4
      Roanoke:40.2
      Piedmont:40.2
      San Antonio:39.9
      Port Arthur:39.8
      Denver-St.:39.8
      Yakima:39.8
      Ft Myers:39.7
      K.C.:39.7
      Birmingham:39.7
      Cheyenne:39.3
      Memphis:39.3
      Norfolk:39.2
      Winnemucca :39.1
      Wichita:39.0
      Norfolk:38.3
      Little Rock:38.3
      Huntsville:37.8
      Chattanooga:37.5
      Concordia :37.5
      Houston:37.0
      New York JFK:36.9
      Lincoln :36.6
      Boise:36.3
      Grand Island:36.2
      Richmond:36.1
      Topeka :35.9
      Nashville:35.8
      Burlington :35.8
      Grand Junction:35.6
      Omaha:35.6
      Pocatello:35.4
      Bristol:35.3
      Miami:35.2
      Memphis:35.0
      W Palm Beach:34.8
      Columbia:34.7
      Knoxville:34.5
      Orlando:34.4
      Atl. City:34.3
      Des Moines:34.3
      Paducah:34.1
      Norfolk:33.9
      Baltimore:33.6
      Victoria:33.6
      North Platte:33.5
      Sioux Falls:33.3
      Rapid City:33.3
      Lander:33.1
      Pendleton:33.0
      Medford:32.9
      Muskegon:32.9
      Sioux City:32.9
      Worcester:32.8
      Bridgeport:32.7
      St Louis:32.5
      Beeville:32.4
      Wilmington:32.2
      Moline:32.2
      Jackson:32.2
      Seattle:32.1
      Omaha:32.1
      Huron:32.0
      Corpus Christi:32.0
      Salt Lake City:31.9
      Waterloo :31.9
      Allentown:31.9
      Milwaukee:31.8
      Lexington:31.8
      Washington DC:31.7
      Rochester:31.7
      Evansville:31.6
      Philadelphia:31.6
      Springfield IL:31.6
      Scottsbluff:31.4
      Mansfield:31.4
      Chicago:31.1
      Harrisburg:31.0
      Providence:30.8
      Madison:30.8
      Boston:30.6
      Houghton Lk:30.6
      Spokane:30.6
      Kingsville:30.5
      Cincinnati:30.3
      Louisville:30.2
      Erie:30.1
      Rockford:30.1
      Peoria:30.0
      Fargo:30.0
      Newark:30.0
      Quantico:30.0
      Salem:29.6
      Eugene:29.6
      Beckley:29.5
      South Bend:29.3
      Columbus OH:29.3
      Williston:29.1
      Grand Rapids:29.1
      Detroit Metro:29.0
      Aberdeen:28.9
      Minneapolis:28.9
      Bismarck:28.8
      Dayton:28.7
      Alpena:28.7
      Akron:28.6
      Ft Wayne:28.5
      Lansing:28.4
      Indianapolis:28.4
      Portland:28.3
      Brunswick:28.2
      Casper:28.2
      Astoria:28.1
      Green Bay:28.1
      Wilkes-Barre:28.0
      Duluth:28.0
      Toledo:27.6
      Sault Ste Marie:27.5
      Flint:26.9
      Youngstown:26.8
      Concord :26.8
      Binghamton:26.5
      Pittsburgh:26.5
      Olympia:26.4
      Glasgow:26.4
      Cleveland:26.1
      Helena:26.1
      Brownsville:26.0
      South Weymouth:25.9
      Billings:25.7
      Barbers Point:25.4
      Rochester:25.4
      Syracuse:25.3
      Quillayute:25.1
      Huntington:24.9
      Hartford:24.8
      Intl Falls:24.8
      Missoula:24.8
      Great Falls:24.5
      Buffalo:24.4
      Lakehurst:23.9
      Albany:23.8
      Charleston WV:23.6
      Williamsport:22.4
      Burlington:19.3
      Lihue:18.5
      Annette Island:16.2
      Valdez:13.2
      Juneau:13.0
      Kodiak:11.8
      Anchorage:11.2
      Fairbanks:10.7
      Homer:10.3
      Honolulu:9.8
      Nome :8.7
      Mcgrath:8.3
      Kotzebue:7.8
      Yakutat:7.2
      Bethel:6.1
      King Salmon:4.1
      Hilo:4.0
      Mt Washington:1.7
      Barrow:0.8
      Cold Bay:0.6
      St Paul Island:0.1
      Barter Island:0.1
      Adak:0.0
      Shemya:0.0

      Delete
  2. The list would be very interesting to redo and change the high temperature reading to the day average temperature and publish the list. What say you?

    ReplyDelete
    Replies
    1. Not sure I understand.Do you mean that each city (station) would have a different ideal temperature threshold based on their average temperature?

      Delete
  3. Thanks for a great post! The images are also awesome!
    If you need long term sound trip then visit the link -
    guys trips

    ReplyDelete
  4. This comment has been removed by the author.

    ReplyDelete
  5. Hi Brian, what a wonderful picture and a very interesting initiative! I live in Belgium where the weather is really horrendous almost all year-round (here it looks like coastal AK, however in a milder version). This picture recalls us how the Southeast states are not so bad that we would think, especially owing to their marvellous springs and falls... I love to practice bicycle and sometimes (especially during summer), the sun can be very oppressive when the conditions are hot(even with 70°F when the humidity is very high).

    Therefore, I am curious to know how would be the result of your work if you except your third point(the cloudiness). In others terms, what could be the results if you don't take the sun into account ???

    Saying that, we cannot forget the hole package of weather conditions. So if 70°F under a clear sky at noon in june, without any wind, and with a humidity close to 100% is nearly the hell, 85°F after dusk with a sustaining breeze and a humidity below 40% is just perfect heaven...

    ReplyDelete

Note: Only a member of this blog may post a comment.