Winter Storm Watch, Advisory, and Warning Criteria for North Texas

When it comes to winter weather, there is no shortage of advisory types.  This page is devoted to the four main winter weather products: Winter Storm Watch, Winter Storm Warning, Winter Weather Advisory, and Ice Storm Warning.  More specifically, I want to discuss the criteria used by the National Weather Service Office in Fort Worth, … Read more

Significant Winter Storm for North Texas Sun Night & Mon (2/22 – 2/23)

Overview: A winter storm is developing for North Texas. I have been monitoring the data very closely for the past few days, and my concern is growing that a problematic sleet & freezing rain event may impact the area beginning Sunday night and continuing through Monday.  On Sunday, temperatures should stay in the 40s as overcast … Read more

Rain and Colder Temperatures on the Way for D/FW

Special Update (Sunday 2/15 8:00 pm) ***Freezing Rain Possible Over Western Parts of North Texas*** ***West of a line from Gainesville to Denton to Fort Worth*** The strong cold front will move through North Texas tonight as predicted in my previous forecasts. Behind the front, temperatures will fall rapidly into the 30s. As of 8 … Read more

Atlanta: Arctic Air on the Way – Winter Precipitation Possible

Update #7  Sunday, February 15, 3:30 pm:  Warmer air will surge in earlier than expected, meaning that only rain will fall in the Atlanta metro on Monday.  Late in the day and overnight, the rain may change to freezing rain and/or sleet, especially east of a Cedartown to Douglasville to Conyers to Athens line (the … Read more

Weather Myths: Too Warm for the Snow to Stick?

Before I begin this piece, I want to present a challenge.  The following chart shows the actual high and low temperatures for a full month in Atlanta, Georgia. *A condensed version of this writeup was also featured in the Douglas County Sentinel. Challenge: Can you spot the day with a historic snowstorm? During this particular … Read more

Birmingham’s Winter Storm Watch, Warning, & Advisory Criteria for Alabama

The National Weather Service has sole responsibility for issuing weather watches and warnings.  When it comes to winter weather, there are numerous advisory types ranging from Wind Chill Advisories to Ice Storm and Blizzard Warnings.  This page is devoted to the four main winter weather products:  Winter Storm Watches, Winter Storm Warnings, Winter Weather Advisories, … Read more

DFW: Rain, windy, & colder Thursday; snow possible Thursday night

(Forecast Posted Tuesday 1/20/15) …Widespread heavy rain & possible winter weather event for North Texas… In my forecast yesterday (Monday), I noted that Thursday’s high temperature would occur at midnight (40s) then fall into the mid 30s for the daytime. This continues to be a very difficult forecast, because there isn’t a preexisting cold airmass … Read more

A Brief History of Weather Forecasting

The Weather Bureau, now known as the National Weather Service, was established on February 9, 1870 by the 41st United States Congress and signed by President Ulysses S. Grant. On March 29, 1870, the new weather forecasting service was officially assigned to the U.S. Army Signal Service within the Department of War and given the … Read more

Coldest airmass thus far will arrive in North Texas Wednesday (1/7)

I’ve been posting updates about this airmass on my Facebook and Twitter pages, but I thought I’d go ahead and write a short discussion about this airmass.  It has the potential to be the coldest air we’ve seen in a year or so, at least when measured by the low temperatures Wednesday night/Thursday morning. Precipitation … Read more

Arctic Airmass Moves into Atlanta by Wednesday (1/7)

Special Update (Wednesday, January 7 at 8 pm EST) Temperatures are already falling into the teens in the western and northern suburbs. Current temperatures are a couple of degrees colder at this hour than model guidance had indicated. Dew points (a measure of atmospheric moisture) continue to drop, and temperatures tonight should certainly be on … Read more

DFW: Freezing Rain Expected Over North Texas Tonight and New Year’s Day

Track the storm with the Weather-Net tools:  Advisories/Warnings | Live & Predictive Radar Special Update (Wednesday 12/31 11:30 pm CST) Precipitation is entering North Texas (use the radar links above to track the precipitation).  Temperatures will fall below freezing after the precipitation begins.  As I posted earlier today, the critical line is the 29º wet-bulb … Read more

Atlanta’s Winter Storm Watch, Advisory, and Warning Criteria for Georgia

As a NOAA Weather-Ready Nation Ambassador, iWeatherNet strives to create educational content to help you be prepared for any type of severe weather; this includes winter weather. I wanted to take the opportunity to briefly review the various winter weather products issued by the Atlanta National Weather Service in Peachtree City. Other States Central Alabama: … Read more

Atlanta: Heavy Rain, Strong Winds, & Severe Thunderstorms Possible

This page was updated on Tuesday 12/23 at 1:17 pm EST:  A Flood Watch has been issued Useful Tools on iWeatherNet:  Advisories | Interactive Radar Christmas Week Forecast/Event Timing: Monday/Monday Night: Rain likely. Temperatures steady in the mid 40s. Tuesday: Dense fog much of the day.  Rain and thunderstorms developing late. Rain increasing in intensity … Read more

Atlanta: Rain Likely Friday Night (12/19) & Saturday Morning (12/20)

A disturbance will bring a cold rain to the Southeast Friday night and Saturday morning (12/19 and 12/20). Simultaneously, some weak cold-air damming will be enhanced by evaporative cooling yielding a very cold/raw day for holiday shoppers, particularly during the morning.  Here are some forecast highlights for those who plan to be out and about: … Read more

DFW: Thunderstorms Expected Sunday Afternoon (12/14)

Fast moving thunderstorms will develop Sunday afternoon and should bring some much-needed rainfall to North Texas.  Below is a brief discussion of our expectations.  If you prefer, you can skip to the forecast summary. Synopsis The vigorous upper-level system that brought heavy rain and snow to portions of the Western U.S. will bring a chance … Read more

Cause of Fireworks Smoke & Fog at the ACC Championship on 12/6/14

If you watched the GA Tech/FSU ACC Championship Game in Charlotte, North Carolina tonight (12/6/14), you may have seen the smoke-filled stadium following the pre-game fireworks show.  A heavy fog was already in place, which virtually guaranteed poor visibility of the fireworks; but to make matters worse, the smoke from the fireworks had no where … Read more

Difference Between Single vs. Multiple Lake Effect Snow Bands

Radar image showing both single and multiple snow bands.

In an earlier article, we discussed the dynamics and thermodynamics of lake effect snow. In this post, we discuss the meteorological differences between single-band and multiple-band lake-effect snow events.  Keep in mind that all lake-effect snow events are fueled by moisture and latent heat flux from the relatively warm lake water; these fluxes are already … Read more

DFW: Quick-Hitting Arctic Front Arrives Monday Morning (12/1)

An unseasonably warm weekend is about to commence over North Texas, with temperatures in the mid to upper 70s.  That will come to an abrupt end first thing Monday morning, with the passage of a very shallow, quick-hitting Arctic front.   Temperatures Monday will be about 40 degrees colder than those of Sunday.  So, get out … Read more

DFW: Thunderstorms with Locally Heavy Rain Today (11/22/14)

A vigorous upper-level disturbance is moving into West Texas this morning.  The trough axis (and associated forcing) will not move east of the area until tonight.  As the system approaches North Texas, a copious amount of Gulf moisture continues to advect into North Texas.  As of 11 am, much of the area has already seen … Read more

Lake-Effect Snow: The Physics of Colossal Snow

Lake effect snow formation illustration

One of the most awe-inspiring forces of nature is lake-effect snow. The amount of latent energy required to produce the lake-effect convection is astounding, and in some situations, snowfall rates can reach as high as 5 to 6 inches per hour.  In this article, we discuss the atmospheric physics, dynamics, and thermodynamics responsible for the … Read more

DFW: Light sleet and light snow still expected this evening (11/16)

The Arctic front is on schedule, and the colder air is filtering into North Texas as of 11 am (Sunday, 11/16).  This map shows temperatures at 11 am. Upper-Air Data (Morning Sounding and Forecast Soundings) Throughout the morning, drizzle and light rain have been falling across North Texas with temperatures in the mid to upper … Read more

DFW: Light Snow Still Expected Sunday Evening (Sunday 11/16/14)

Published Friday, November 14 at 3:50 pm: Earlier this week, I posted about the potential for light snow on Sunday evening.  The forecast has not changed.  However, because of the timing of the precipitation Sunday evening (after temperatures drop to freezing), I am adding some light accumulations.  The greatest chance for accumulating snow is north … Read more

DFW: Scattered Areas of Light Sleet Expected Tonight (Wed 11/12)

This will be a very brief update to mention the possibility of very light sleet in North Texas tonight.   An upper-level disturbance is moving into Texas, and will provide sufficient (albeit weak) forcing for precipitation.  Temperatures will fall to near freezing in the metroplex and below freezing for areas north of Denton by 10 pm.  … Read more

DFW: Light Snow Possible Sunday Evening With Reinforcing Shot of Arctic Air

For the past 5 days, I have been closely monitoring a disturbance that will move across North Texas on Sunday/Sunday night.  Every meteorologist who has been watching the model data is fully aware of the “accumulating snow” that some of the models have suggested over the past week.  One thing that legitimate meteorologists typically do … Read more

Strong Cold Front To Reach Atlanta Wednesday Evening

The long-awaited cold front will finally reach the Atlanta metro tomorrow evening (Wednesday 11/12). At this time, it still appears that the front will move through the Atlanta area during the early-evening hours. After reaching the mid 60s on Wednesday, Atlanta will be 20 degrees colder on Thursday with highs only in the mid 40s. … Read more

Heavy Rain and Colder Temperatures for DFW on Tuesday 11/4/14

A strong cold front will move through North Texas on Tuesday (11/4/14). The timing of the cold front, and rain amounts may need to be modified with future data. At this time, these are my expectations: Ahead of the front Tuesday morning, temperatures should be 65º to 70º. Temperatures will fall 15 to 20 degrees … Read more

Atlanta: First Freeze for the Southeast Still Expected

As predicted, the strongest cold front so far this season is moving south through the Midwest, and will arrive in the Birmingham/Atlanta areas this evening.     10/31 12:52 pm Forecast Update: The cold front will be moving through around 7 pm. Temperatures will fall into the 40s, especially after 8 pm. The wind will … Read more

Atlanta’s Strongest Cold Front so far this Season by Halloween Weekend

Wednesday, October 22, 2014 – There are indications that the first freeze of the season may occur in about 10 days from now (around Halloween/Nov 1/2/3).  Stay tuned for future updates. Update #1 – Thursday, October 23, 2014  ***Strongest cold front so far this season one week from tomorrow (Halloween) followed by the first freeze*** … Read more