Monday, August19, 2019

Marine Weather and Tides
Nevada, IA

Version 3.4
7/25/2019 New feature in the Airports section gives a link to 5 minute updates for data reports.
6/2/2019. Many thanks to a user for reporting an error on one of the Edit pages. The switch to PHP 7.2 caused many pages that previously worked to quit working. I fixed many but I still depend on users to report ones I missed. Please report errors HERE or send an email to me at Allen

Sunrise 6:25AMSunset 8:11PM Monday August 19, 2019 10:37 PM CDT (03:37 UTC) Moonrise 9:27PMMoonset 9:11AM Illumination 79% Phase: Waning Gibbous; Moon at 19 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 Nevada, IA
   Hourly   EDIT   Help
location: 42.02, -93.46     debug

Area Discussion for - Des Moines, IA
      (on/off)   Help   NOTE: mouseover dotted underlined text for definition
Fxus63 kdmx 200244
area forecast discussion
national weather service des moines ia
944 pm cdt Mon aug 19 2019

Issued at 942 pm cdt Mon aug 19 2019
the active night still appears to be on target with little change
from previous thinking. 4-5k j kg mucapes are present along the
ne ia border in the projected genesis area with 40-45kts of
effective shear. The only concern may be slightly delayed timing
and onset. 00z soundings and the latest model guidance do not
depict the strongest low level jet with rap 305k inflow into the
base of the effective layer only 20kts or so. Nevertheless, once
it GOES it may go quickly with fresh 00z cams all still depicting
a significant wind producing MCS nw-se starting 06-09z and not
exiting southeast sections until 12z or so. If this caliber of mcs
develops as expected, it will be somewhat rare in magnitude
reflecting the infrequency of overnight enhanced risks in ia.

Possibly reminiscent of significant wind events in 2008 or 2010.

Discussion tonight through Monday
issued at 309 pm cdt Mon aug 19 2019
high pressure remains ridged into central iowa this afternoon with
return flow beginning to develop into far western iowa and into
nebraska and kansas. The return flow will increase this evening as
the high departs to the east. The low level jet will form and
increase to 35-40kts between 03-06z and will bring a strong push of
theta-e advection into central iowa. This combined with steepening
mid-level lapse rates will lead to moderate to highly unstable
environment with mucapes exceeded 3500 j kg. Expect thunderstorms to
develop across portions of northwest to west central iowa around
midnight then roll southeast down the instability gradient. Severe
weather and heavy rain fall will both be concerns with this activity
overnight. Initial storms will be elevated with a few supercells
capable of large hail possible. The initial cells should congeal
into an MCS and propagate southeast with an attendant damaging wind
threat into central and southeast iowa. In addition, an isolated
tornado or two may be possible given the amount of low level SRH if
the 0-3 km shear vector can orient correct in time. This would be
contingent on potential for increased mixing ahead of the line can
help erode the low level inversion and allow for low level vortex
stretching. A few areas of wind driven hail may occur given the
maintaining instability and potential for cold pool development.

The potential for heavy rainfall is increasing as the increasing
instability within a moisture rich atmosphere with good warm cloud
depths near 15 kft aiding in the efficient rain process. A rainfall
band of 2 to 4 inches is possible and cannot discount a heavier
localized band in excess of 5 inches. The intense rainfall amounts
will cause significant ponding in urban areas. If a 5 inch band does
develop, the threat may translate to a flash flooding threat given
the rates and amounts.

Warm advection following the the morning MCS will create a
significant elevated mixed layer that will lead to a significant cap
across the state. Convective debris looks like it will eventually
clear out over parts of the state. The biggest challenge will be how
much of the state will recover from the morning outflow. Have the
warmest temperatures over central and western iowa with high
temperatures approaching 90 degrees and heat index values in the 100
to 105 degree range. Not anticipating any heat headlines at this
point especially considering uncertainties given the recovering.

Have lowered chances for thunderstorms Tuesday afternoon and
evening. A greater threat for storms will late Tuesday night into
Wednesday morning over as storms move east out of nebraska.

Little change to the remainder of the forecast with cooler
temperatures Thursday through Saturday then a transition to more
westerly flow by Sunday into early next week. This will lead to
seasonal temperatures and a few more chances for precipitation.

Aviation for the 00z tafs through 00z Tuesday evening
issued at 637 pm cdt Mon aug 19 2019
there is high confidence inVFR conditions into the evening, but
also at least medium confidence that a significant thunderstorm
complex will develop into portions of central ia during the early
morning hours. HaveVFR vcts mention for now, but there will
likely be a period of lower conditions for at least one of the
taf sites overnight. No mention until timing and location
confidence increases however. Some lingering stratus is possible
after the precip, but confidence is medium to high thatVFR
conditions will return by Tue afternoon.

Dmx watches warnings advisories

Update... Small
discussion... Donavon
aviation... Small

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. Follow links for more data.
AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Ames, Ames Municipal Airport, IA9 mi1.7 hrsE 410.00 miFair73°F69°F87%1014.4 hPa
Boone Municipal, IA21 mi1.7 hrsESE 710.00 miFair72°F71°F100%1014.9 hPa
Ankeny Regional Airport, IA24 mi1.7 hrsESE 410.00 miFair73°F69°F89%1015.2 hPa

Link to 5 minute data for KAMW

Wind History from AMW (wind in knots)
Last 24hrNE4N3Calm--N5----N4N3N4NE5E4--3NE5SE5SE7----SE5E4SE4E3E4
1 day agoSE6S3S5SE6Calm--W5S3SE15
2 days agoCalm--Calm--CalmS6--CalmCalm----SE5CalmNE3E3SW7S7S6SE8SE5SE7SE8SE6SE5

Tide / Current Tables for
   EDIT   Weekend mode (on/off)   (on/off)   Help
Tide / Current Tables for
   EDIT      (on/off)   Help
Weather Map and Satellite Images
       (on/off)   HelpWeather Map
GOES Local Image of    EDIT
NOTE: East coast views moved to GEOS-16. They are experimental and not well supported by NOAA so they may not be correct so be warned. This change required redoing a large amount of the GOES code. If the image you are expecting is not showing, please let me know. You may need to use the EDIT function to update your location.
Link to Loop

Other links: Northern Pacific     Contential US     Full GOES-East
Wind Forecast for Des Moines, IA (23,6,7,8)
      (on/off)   Help

Ground Weather Radar Station Des Moines, IA
   (on/off)   Help
weather_mapweather_map weather_map

Ad by Google

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 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 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.