21 Days until Christmas! Keep giving thanks to be living in the best time of human history.......every day of the year!
Scroll down and enjoy the latest comprehensive weather to the max...... occurring because of the natural physical laws in our atmosphere as life on this greening planet continues to enjoy the best weather/climate in at least 1,000 years(the last time that it was this warm) with the added bonus of extra beneficial CO2.
Cold blast hitting late this weekend into next week.
Forecasts for GFS ensemble were colder overnight, boosting ng. Unreliable 12z GFS operational model milder. ensembles around the same, so we are holding gains.
Winter Weather Forecasts
https://www.wpc.ncep.noaa.gov/wwd/winter_wx.shtml
Snowfall the next 7 days below.
Here are the latest hazards across the country.
Purple/Pink/blue on land is cold/Winter weather. Brown is wind, Green is flooding. Gray is fog. Reddish is a red flag advisory.
Go to the link below, then hit the location/county on the map for details.
https://www.spc.noaa.gov/ Go to "hazards"
https://www.mesonet.org/index.php/weather/map/us_air_temperature/air_temperature
https://www.mesonet.org/index.php/weather/map/wind_chill_heat_index1/air_temperature
Current Weather Map
| NCEP Days 0-7 Forecast Loop | NCEP Short-Range Model Discussion | NCEP Day 3-7 Discussion |
Current Jet Stream
| Low Temperatures Tomorrow Morning |
Highs today and tomorrow.
Highs for days 3-7:
A brand new blast of frigid air drops south, starting Sunday.
Temperatures vs average for days 3-7.
Very mild most places............then turning frigid far north on day 3!....heading south.
https://www.wpc.ncep.noaa.gov/medr/medr_mean.shtml
Weather features day 3-7:
Strong cold front/blast on Sunday. Much colder next week.
Liquid equivalent precip forecasts for the next 7 days are below.
Mostly dry Midwest the rest of this week.
Day 1 below:
http://www.wpc.ncep.noaa.gov/qpf/fill_94qwbg.gif?1526306199054
Day 2 below:
http://www.wpc.ncep.noaa.gov/qpf/fill_98qwbg.gif?1528293750112
Day 3 below
http://www.wpc.ncep.noaa.gov/qpf/fill_99qwbg.gif?1528293842764
Days 4-5 below:
http://www.wpc.ncep.noaa.gov/qpf/95ep48iwbg_fill.gif?1526306162
Days 6-7 below:
http://www.wpc.ncep.noaa.gov/qpf/97ep48iwbg_fill.gif?1526306162
7 Day Total precipitation below:
https://www.wpc.ncep.noaa.gov/qpf/p168i.gif?1566925971
Current Dew Points
Latest radar loop
http://www.nws.noaa.gov/radar_tab.php
| (3400x1700 pixels - 2.2mb) Go to: Most Recent Image |
Go to: Most Recent Image
You can go to this link to see precipitation totals from recent time periods:
https://water.weather.gov/precip/
Go to precipitation, then scroll down to pick a time frame. Hit states to get the borders to see locations better. Under products, you can hit "observed" or "Percent of normal"
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Soilmoisture anomaly:
These maps sometimes take a day to catch up to incorporate the latest data(the bottom map is only updated once a week).
https://www.cpc.ncep.noaa.gov/products/Soilmst_Monitoring/US/Soilmst/Soilmst.shtml#
Drought Monitor maps:
Latest: The first map below is the latest. The 2nd one is from last week.
In july/August/Sept/Oct, it's typical to see some increase in drought because of evaporation, seasonally exceeding low rainfall during those months. However, this year saw a HUGE increase in the Southeast!
December 5: DROUGHT the last 2 months has really shrunk. One area to watch is sw Kansas and S.Plains for the Winter wheat crop but it's going dormant right now.
The maps below are updated on Thursdays.
https://droughtmonitor.unl.edu/
The top map is the Canadian ensemble average, the maps below are the individual members that make up the average at the end of week 2.
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Each member is like the parent, Canadian model operational model.......with a slight tweek/variation in parameters. Since we know the equations to represent the physics of the atmosphere in the models are not perfect, its useful to vary some of the equations that are uncertain(can make a difference) to see if it effects the outcome and how.
The average of all these variations(ensembles) often yields a better tool for forecasting. It's always more consistent. The individual operational model, like each individual ensemble member can vary greatly from run to run.........and represent an extreme end of the spectrum at times. The ensemble average of all the members, because it averages the extremes.............from opposite ends of the spectrum.........changes much less from run to run.
End of week 2....................0z Canadian ensembles:
Updated 12z maps available this late...........turning colder late week 2 vs previous solutions. Potential for another polar vortex incursion south...on some solutions, mainly this particular model!
Staring with last week below:
Friday: Zonal, mild west to east flow. Pretty strong agreement.
Saturday: No change from yesterday.
Sunday: Major cold still cut off.
Monday: Noteworthy changes in the last 24 hours, all of them colder but not yet extremely cold. More troughing in the middle of the country on the mean below and possible cross polar flow......or at least high Arctic north to south flow on this side of the N.Hemisphere dumping extreme cold into Canada to replace previously mild conditions there. This means cold fronts can be REALLY cold now in week 2 vs a moderate brand of mild (for Winter) Canadian cold.
Tuesday: Similar to Monday
Wednesday: Modest ridge West/trough downstream, similar to before. Will mild Pacific flow/southern stream(with upper ridge in very far Southeast?) or colder northern stream dominate. A battle will be taking place with big changes/fluctuations.
Thursday: Similar to recent days. Battle between northern and southern stream. A tad more upper level ridging far southeast on some members.
360h GZ 500 forecast valid on Dec 20, 2019 00 UTC
Forecasts for the control (GEM 0) and the 20 ensemble members (global model not available)
0Z GFS(American model) Ensembles at 2 weeks:
GFS Ensemble mean(average of all the individual solutions above). The first map is a mid/upper level map. The 2nd one is a temperatures map at around 1 mile above the surface. These are anomalies(difference compared to average).
NCEP Ensemble t = 360 hour forecast
Thursday: Good ridge/west, trough east couplet in Canada to force cold to move south thru Canada to Northern US. Not as favorable dynamics for cold as you head farther south. 
Latest, updated graph/forecast for AO and NAO here, including an explanation of how to interpret them...............mainly where they stand at the end of 2 weeks.
Previous analysis, with the latest day at the bottom for late week 2 period.
https://www.marketforum.com/forum/t
Discussions, starting with a week ago.
Last Sunday: Huge AO changes. Many members go very strongly positive which lessens cold air outbreak probabilities. However, some are still negative, so an incredible spread and uncertainty. NAO increasing from low values to a tad above 0.........also lessening cold risks at 2 weeks. PNA near 0. Cold risk after the first week in December have decreased.
Monday: Very positive AO decreases chances for cold from high latitudes moving to the middle latitudes. NAO moving to slightly positive is also a potential mild indicator. PNA close to zero but dropping a bit late.
Tuesday: AO spikes extremely positive, then comes back down towards zero in week 2. NAO slightly positive, PNA near zero.
Friday: Very Positive AO and NAO mean mild temps/no cold air delivery from the north. Dropping late week 2 but still positive. PNA decreases from positive to just below 0 late.
Saturday. Positive AO but a change from yesterday late week 2 as it plunges. Mainly from several members fairly negative. The actual pattern still favor +AO regime. NAO is also positive/mild but drop towards 0 at the end of 2 weeks. PNA slightly positive. Overall, at least well into week 2, indicators are favorable for mild temps.
Sunday: AO and NAO stay positive thru 2 weeks(some fairly positive values early in the period) this makes frigid outbreaks extremely unlikely. PNA slightly positive(warm West)
Monday: AO drops down to near zero by then end of week 2 for the first time in a long while.........portending a potential change that allows frigid air to move from high latitudes southward. Still slightly +NAO will make it tough for that cold to penetrate deeply south and east. Slight positive PNA with modest ridging out West(warm and dry).
Tuesday: Similar to Monday. AO and NAO still stay just above zero which makes the extent of the cold outbreaks uncertain.
Wednesday: AO, NAO and PNA are all positive but close to zero at the end of 2 weeks, so not powerful indicators then.
Thursday: Positive AO and NAO drop towards 0 late week 2. PNA a tad positive. Nothing profound to affect forecast philosophy in a meaningful way.
National Weather Service 6-10 day, 8-14 day outlooks.
Updated daily just after 2pm Central.
Temperature Probability
Precipitation Probability
| the 8-14 day outlooks ArchivesAnalogsLines-Only FormatGIS Data | |
Temperature Probability | |
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Just for entertainment, let's look at the just updated European model monthly- 768 hour- outlook, 850 mb temperatures, which is around a mile up. Starting with December 16th and going out to January 5th...... every 24 hours.
The big cold snaps on the last run that were to start hitting just before Christmas are not there on this run.
