Arctic air mass will arrive into SE TX late this weekend.
Preparations for an extended period of cold weather should be completed this weekend.
Winter precipitation is possible early to mid next week.
Cold air mass over northern Russia and Siberia will move across the north pole and into northern Canada over the next few days before dropping quickly southward down the plains under the influence of a large sprawling 1040-1050mb surface high pressure dome. The overall setup is a fairly classic arctic air dump into the southern plains and Texas…but as usual the fine details of how cold, for how long, and will there be any precipitation, what kind, and how much are the usual challenges with such events. There has not been much change in the thinking in the last 24 hours and the global model guidance has not shown much change on the temperatures…maybe a few degrees warmer. We will start to get into the high resolution guidance over the next few days which will help better resolve the intensity of the incoming air mass so until then there will likely not be any significant changes to the temperature forecasts.
Initial cold front will move through on Saturday with a chance of showers (mostly east of I-45) and then gusty northerly winds and falling temperatures into the afternoon and evening hours. Temperatures Sunday AM fall into the 30’s for much of the area, but above freezing for nearly all for the metro area…wind chills will be cold however in the 20’s and 30’s. True arctic air mass arrives late Sunday into early Monday with temperatures falling below freezing for much of the area Monday AM being driven by gusty northerly winds and strong cold air advection. Wind chill values on Monday morning likely in the 10’s and 20’s with a “cold weather advisory” likely required for much of the area. Temperatures going forward on Monday into Tuesday will be somewhat dependent on the amount of cloud cover and any precipitation over the area. Looks like clouds will build in from the southwest through the day on Monday which will slow heating along with continued cold air advection into the area. Highs in the upper 30’s to low 40’s currently in the forecast, but this may need to be lowered some if clouds come in faster than expected. Much if not all of the area will fall below freezing again Monday night into Tuesday morning and this is where things begin to get a little tricky as the potential for precipitation develops and this could keep highs on Tuesday very cold (near freezing for much of the area). For now, will go along with the blend of guidance and have highs in the mid/upper 30’s but would not be surprised to see these numbers lowered depending on the amount of clouds and precipitation.
While it will be cold…there is nothing currently to suggest this will be anywhere close to the intensity of the cold nor the duration of the Feb 2021 event!
Monday AM Forecasted Low Temperatures:
North of HWY 105: 23-26
North of I-10: 27-30
Houston metro (inside Beltway): 28-30
Coastal Counties: 29-31
Beaches/Galveston: 32-34
Winter Precipitation:
Just when the global guidance was starting to come into better agreement on the potential for winter precipitation yesterday it has all fallen apart overnight with widely varying solutions from little to no precipitation at all to a cold rain to ice/snow. An upper air disturbance will move toward Texas in the Mon-Tues time period with a coastal low forming off the lower TX coast likely on Monday. This setup is not all that different from the coastal low event last week, except is looks about 5-8 degrees colder which introduces the potential for a winter mix of precipitation types over the region. The position of the coastal low along with the available moisture will be the key on what we can expect early to mid next week. Thermal profiles between models are not in any better agreement which would help to determine the P-type…and while the blend of models has slightly increased the chances of precipitation early next week there is little confidence in how this may play out, what may be the dominant type of precipitation and any accumulations. Will have to see how future trends go and await the higher resolution guidance over the weekend to see if a better picture evolves on how things will come together early next week.
Preparations:
Proper winterization preparations will be needed for this cold air outbreak and will need to be completed by this weekend.
- Protect sensitive vegetation.
- Protect any exposed outdoor pipes (sprinkler systems should be shut off and properly drained).
- Prepare proper shelter and warmth for animals and livestock and make sure water sources do not freeze over.
- Persons should limit outside exposure to a minimum.
