Monday, May29, 2017 L-36.com


Marine Weather and Tides
Yankton, SD

Version 3.4
What's New / NOTES
5/23/2017 - Worked with NOAA again to speed up the 7 day forecast load times. Thanks to them for being responsive.
5/19/2016 - There were issues with the 3 day airport observation history. I switched to another data source. Let me know if you see any issues with the data feeds.

Sunrise 5:47AMSunset 9:01PM Monday May 29, 2017 10:39 PM CDT (03:39 UTC) Moonrise 9:06AMMoonset 11:49PM Illumination 21% Phase: Waxing Crescent; Moon at 5 days in cycle
NOTE: Some of the data on this page has not been verified and should be used with that in mind. It may and occasionally will, be wrong. The tide reports are by xtide and are NOT FOR NAVIGATION.
Marine Forecasts
    EDIT      (on/off)   Help
7 Day Forecast for Marine Location Near Yankton, SD
   Hourly   EDIT   Help
location: 42.89, -97.39     debug


Area Discussion for - Sioux Falls, SD
      (on/off)   Help   NOTE: mouseover dotted underlined text for definition
Fxus63 kfsd 300323
afdfsd
area forecast discussion
national weather service sioux falls sd
1023 pm cdt Mon may 29 2017

Short term (this evening through Tuesday)
issued at 344 pm cdt Mon may 29 2017
scattered showers are occurring this afternoon primarily in
southwest mn as expected. The soundings are not displaying as much
of an inverted v currently as they were Sunday afternoon, with
pretty deep moisture from 850-600mb. Therefore convective winds have
been subdued. The synoptic winds are quite brisk however, but will
greatly subside after sunset. More challenging is what to do with
the cloud cover. There is a discernible short wave on water vapor,
currently over north central sd and moving southeastward. Some of
this cumulus will disappear as the daytime heating subsides on the
periphery of the very large upper low northeast of our cwa. However
throughout the northeast quarter of our forecast area, clouds may
have a tougher time totally disappearing where the depth of moisture
is deeper and the short wave expected to have a greater influence.

Lows will be chilly tonight. In our west, preferred the coldest
guidance numbers such as mos, and even dropped them a bit from mos
values with very light dry winds and clear skies anticipated toward
central sd. Elsewhere, consensus lows did not look too bad but still
favored the cooler guidance readings. So once again, there will be a
lot of widespread 40s. On Tuesday, one more day of chilly cool
weather, with what will likely be another festival of cumulus
developing across the northeast half of our area, due to cold air
aloft and ample moisture from 800-700mb. Large upper low still in
southeast canada and the great lakes region will provide the
cyclonic flow aloft, and there could be a vort filament extending
into southwest mn during the afternoon. Therefore changed the
sprinkles to some isolated light showers in southwest mn and extreme
northwest ia in case a few showers measure rainfall. Highs on
Tuesday will vary from the lower 60s in southwest mn, to the lower
70s in the mo river valley, similar to today with similar 850mb
temperatures. The northwest winds will once again be very brisk,
averaging 20 to 35 mph with mixed layer winds of 30 knots.

Long term (Tuesday night through Monday)
issued at 344 pm cdt Mon may 29 2017
cyclonic northwest flow will transition to southerly on Wednesday as
high pressure moves across the area. This will promote light winds,
but temperatures will remain below normal with 850 hpa temps in the
single digits. As low level jet develops across the plains on
Wednesday night, could see some elevated showers and thunderstorms
develop. Atmospheric lapse rates are nearly moist-adiabatic, so not
much in the way of instability.

Secondary warm front lifts north Thursday possibly becoming the
focusing mechanism for a few more storms across the region. With the
passage of the front, will also see temperatures nudge closer to
seasonal norms. Friday appears to be the warmest day of the week
with temperatures peaking a few degrees above normal. Strong back
door cold front is expected Friday night and with the passage of the
front could see an additional chance for precipitation. Have some
lingering pops in for Saturday based on ECMWF output, but chance of
precipitation may be overstated as upper level ridge builds in from
the north leading to quiet weather. Temperatures appear to be below
normal, but how cool remains uncertain with the ECMWF running about
5 degrees c cooler than the GFS at 850 hpa. For now, left blend as
is, which is erring towards the warmer side of possible solutions.

Aviation (for the 06z tafs through 06z Tuesday night)
issued at 1015 pm cdt Mon may 29 2017
vfr conditions expected through the period. Another day with
gusty northwest winds up to 25 kts and cumulus at or around 6000
feet is expected Tuesday.

Fsd watches warnings advisories
Sd... None.

Mn... None.

Ia... None.

Ne... None.

Short term... Mj
long term... Bt
aviation... Ferguson jm


Weather Reporting Stations
   EDIT       (on/off)   Help   NOTE: Click on distance to see the station location on a map

Airport Reports
    EDIT      (on/off)   Help   Click EDIT to display multiple airports
AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Yankton, Chan Gurney Municipal Airport, SD2 mi44 minNNW 610.00 miFair55°F45°F69%1017.2 hPa

Wind History from YKN (wind in knots)
11
PM
12
AM
1
AM
2
AM
3
AM
4
AM
5
AM
6
AM
7
AM
8
AM
9
AM
10
AM
11
AM
12
PM
1
PM
2
PM
3
PM
4
PM
5
PM
6
PM
7
PM
8
PM
9
PM
10
PM
Last 24hrCalmSW6N3NW4W4NW8W8W9NW9NW8NW13--NW20
G27
W22
G27
NW18
G26
NW23
G28
NW22
G29
NW14
G24
NW18
G24
NW14
G23
NW14NW10NW4N6
1 day agoSW6SW6SW8SW7W6W11W10SW6W6W8W10NW13
G21
W13NW14
G21
NW21
G30
NW18
G22
NW19
G22
--NW12NW14
G18
W15W8W9N7
2 days agoW3NW3NW3CalmCalmCalmW8NW7NW3SE3N3NW4NW4NW4W5NW7N6W7NW9W11W6SW6W7SW6

Tide / Current Tables for
   EDIT   RT Ports Option   Weekend mode (on/off)   (on/off)   Help
Tide / Current Tables for
   EDIT      (on/off)   Help
Weather Map and Satellite Images
       (on/off)   Help
Weather Map
wmap_A
IR Satellite Image from GEOS
east_satellite

GOES Local Image of Midwest    EDIT
Geos

Wind Forecast for Sioux Falls, SD (23,6,7,8)
      (on/off)   Help

Ground Weather Radar Station Sioux falls, SD
   (on/off)   Help
weather_mapweather_map weather_map

Ad by Google

Disclaimer:
The information on this web site has not been checked for accuracy. It is for entertainment purposes only and should be independently verified before using for any other reason. There are five sources. 1) Documents and manuals from a variety of sources. These have not been checked for accuracy and in many cases have not even been read by anyone associated with L-36.com. I have no idea of they are useful or accurate, I leave that to the reader. 2) Articles others have written and submitted. If you have questions on these, please contact the author. 3) Articles that represent my personal opinions. These are intended to promote thought and for entertainment. These are not intended to be fact, they are my opinions. 4) Small programs that generate result presented on a web page. Like any computer program, these may and in some cases do have errors. Almost all of these also make simplifying assumptions so they are not totally accurate even if there are no errors. Please verify all results. 5) Weather information is from numerious of sources and is presented automatically. It is not checked for accuracy either by anyone at L-36.com or by the source which is typically the US Government. See the NOAA web site for their disclaimer. Finally, tide and current data on this site is from 2007 and 2008 data bases, which may contain even older data. Changes in harbors due to building or dredging change tides and currents and for that reason many of the locations presented are no longer supported by newer data bases. For example, there is very little tidal current data in newer data bases so current data is likely wrong to some extent. This data is NOT FOR NAVIGATION. See the XTide disclaimer for details. In addition, tide and current are influenced by storms, river flow, and other factors beyond the ability of any predictive program.