It’s official—Texas had its warmest winter

It’s official, both Lousiana and Texas had their warmest winters on record. According to NOAA, Louisiana had an average temperatures 6.8 degrees Fahrenheit above average, and Texas was 5.7 degrees above average. From the graphic below it’s not hard to find the culprit for the warm temperatures—the Gulf of Mexico—heated at least in part due to a warming climate.

Average temperature percentiles. (NOAA)

Now let’s jump into the forecast, which will show a hint of cooler weather for next week, and a mostly pleasant Spring Break week.

Today

Temperatures are in the mid- to upper-60s this morning across Houston, and this is helping to cause some fog over the sea and for areas near the coast. It should clear by mid-morning. Skies should remain mostly cloudy during the afternoon hours, with highs climbing into the upper 70s. With the moisture now coming back and an unstable atmosphere, we’re going to be returning to a pattern where thunderstorms are possible later today, although I think most of the region will probably remain dry.

(Space City Weather is sponsored by an anonymous donor this month.)

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Why do meteorologists use different dates for seasons?

Last week, many meteorologists celebrated March 1 as the beginning of spring. Other than the “wait, did we even have winter?” reaction from some, others wondered why we say spring begins then, and not on March 21 (also known as the Vernal Equinox). The confusion stems from the two ways meteorologists classify seasons: meteorological seasons, versus astronomical seasons. What’s the difference? Why do meteorologists use one instead of the other?

Astronomical Seasons

The earth’s rotation around the sun, as well as the earth’s tilt, create the astronomical seasons. For example, at the Vernal Equinox (March 20-22, depending on the year), both the northern and southern hemispheres face the sun at the same angle. Both hemispheres, therefore, get the same amount of solar energy.

As the earth revolves around the sun, we reach the Summer Solstice (June 20-22), the earth’s tilt causes the northern hemisphere to face the sun more directly. This means longer days, more energy from the sun, and therefore, warmer temperatures. The southern hemisphere receives less direct radiation from the sun, which means shorter days, less energy, and cooler temperatures.That’s why Australia experiences winter when we experience summer.

Three months later, at the Autumnal Equinox (September 21-23), the situation is similar to the Vernal Equinox. Both hemispheres receive equal amounts of energy, and face the sun at the same angle. Finally, at the Winter Solstice (December 20-22), the northern hemisphere faces away from the sun–so the days are shorter, the sun’s energy is less direct, and therefore, the temperatures are cooler. Meanwhile, Australia bakes (more so than usual) during their summer.

Diagram of the astronomical seasons (courtesy NASA)

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Expect more showers Friday and Saturday before Houston clears next week

Let’s face it, Tuesday’s cool front hasn’t done a whole lot of cooling. While some parts of Houston have fallen into the upper 50s, most of the central and southern part of the region have only fallen into the low 60s. We’ll have to wait until this weekend for a somewhat stronger front.

Today

Mostly cloudy skies and an easterly wind should hold temperatures today down to about 70 degrees, but there should be no rain. Clouds and winds shifting to the southeast tonight will preclude overnight lows from falling further than into the mid-60s for all but far inland areas.

Thursday

While we can’t rule out the possibility of some scattered showers on Thursday, as moisture levels rise, it looks like most of the area will remain dry. Skies will again be mostly cloudy, with temperatures rising into the mid- to upper-70s.

Friday and Saturday

A combination of increased moisture levels, and lower pressure systems moving in from the west will lead to the likelihood of rain showers and potentially some thunderstorms on both Friday and Saturday. In terms of accumulations I don’t think the area will be looking at more than 1 to 2 inches of rain—with isolated totals a bit higher than that—during the end of the week.

NOAA rain accumulation forecast for now through Sunday morning. (Weather Bell)

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Storms possible today, and rain returns later this week to Houston

It’s another warm morning across Houston, with temperatures generally having fallen only to about 70 degrees. The main concern today will be the possibility of some storms and heavy rain along with the passage of a cold front.

Today

A cold front now in north Texas will move down toward the Houston area, likely pushing through the city during the mid-afternoon hours, and the off the coast by late afternoon. Due to decent moisture levels and and lift associated with the front, much of the area is likely to see some moderate to briefly heavy rain with the front’s passage. I’m expecting on the order of 0.5 inch to 1.0 inch or so, late this morning and during the afternoon hours. The storms may slow, or even stall along the cost, producing more rain there. Along with the front there will likely be some embedded thunderstorms, and a slight chance of some hail. After the front passes tonight look for temperatures to fall into the mid- to upper-50s.

(National Weather Service)

Wednesday

With northerly winds and partly cloudy skies the day will be moderately cooler, with highs in the low 70s. A very slight chance of rain returns during the late afternoon and evening hours. Most of the cooler air is gone by Wednesday night, allowing low temperatures to fall only into the 60s.

(Space City Weather is sponsored this month by an anonymous donor.)

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