Lowest humidity ever recorded: Has the relative humidity ever dropped to zero percent? – Chicago Tribune

A World Record Low Humidity? 116°F With a 0.36% Humidity in Iran

Above:  A screen shot of the observations on June 20, 2017, from Safi-Abad Dezful, Iran, where the temperature hit 46.5°C with a -33.2°C dewpoint at 12 UTC, giving this city of 420,000 in western Iran a ridiculously low relative humidity of 0.36%. Image credit: OGIMET.

On Tuesday afternoon at 12 UTC on June 20, 2017, the temperature at Safi-Abad Dezful, Iran hit 115.7°F (46.5°C) with a -27.8°F (-33.2°C) dewpoint, giving this city of 420,000 in western Iran a ridiculously low relative humidity of 0.36%. At that level of atmospheric moisture, the temperature would have had to plunge 143°F (80°C) in order for the moisture to condense out and form ground-level clouds. If one were to cry in joy (or more likely) in despair at the heat, I doubt those tears would reach your lips!

I asked weather records expert Maximiliano Herrera about the reading, and he stated that he confirmed the validity of the reading with Iranian meteorologist Sabit Siddiqi. This was the lowest humidity in world recorded history that Herrera was aware of; the previous lowest humidity he knew of was in Las Vegas, Nevada: a 0.6% reading on June 27, 2011. He gave credit to Georgian climatologist Evgeny Gavrilov for calling his attention to the new Iranian low humidity event.

However, Steven D. Hilberg, Senior Climatologist for the U.S. Midwestern Climate Center, wrote me this morning to tell me that on May 4, 2014, Needles, California hit 102°F (38.9°C) with a -36°F (-38°C) dewpoint, which works out to a relative humidity of 0.33%. Given that we can’t really measure humidity to a precision of hundreths of a percent, the two readings are pretty much tied for the lowest humidity record. If anyone finds a similar or lower value, please let me know!

Needles, California made another respectable run at the world record for lowest humidity at 12:56 pm PDT, on Wednesday, June 21, 2017, when the temperature hit 119°F (48°C) with a -11°F (-24°C ) dewpoint, for a relative humidity of 0. 8%. The preliminary high temperature in Needles on Wednesday topped out at a relatively cool 122°F. The previous day, June 20, 2017, Needles tied their all-time hottest temperature on record: 125°F. We’ll have more on the record-smashing Southwest U.S. heat wave in a post later this week.

World record hottest overnight low temperature: 111°F in Oman on June 17

As we reported on Monday, it’s been a remarkable few weeks for heat in the Middle East and Southwest Asia, with three nations—Pakistan, Oman and the United Arab Emirates—setting their all-time hottest temperature records between May 28 and June 16, 2017. To add to the list of extraordinary recent heat events there, we now have a world record for hottest overnight low temperature: a minimum temperature of 111.6°F (44.2°C) recorded on the morning of June 17, 2017 at Khasab, Oman, located on the Persian Gulf. According to Herrera, the incredible overnight heat was made possible by a strong foehn wind that was blowing downslope from a mountain that Khasab sits at the base of. Descending winds heat up the air by compression as it is forced downward, and many all-time record warm temperatures are set during foehn events.

The previous world record for hottest nighttime low temperature was 107.4°F (41.9°C) on 27 June 2011—also recorded at Khasab. Khasab Airport also holds the record of highest minimum temperature in 24 hours (from 7am to 7am) with 107.4°F (41.9°C) on 27 June 2011, which was also the previous nighttime world record. Thanks go to Dr. Michael Theusner of Klimahaus for alerting us to the new record at Khasab.

Figure 1. A burned car stand next to burned houses after a wildfire took dozens of lives on June 18, 2017 near Castanheira de Pera, in Leiria district, Portugal. Most of the victims died in their cars while trying to flee the flames. Photo by Pablo Blazquez Dominguez/Getty Images.

Portugal’s wildfires: the 11th deadliest in world recorded history

The death toll in last weekend’s horrific fires that roared through a forested area in central Portugal is now 64. According to EM-DAT, the international disaster database, Portugal’s fires now rank as the world’s 11th deadliest wildfire event in recorded history. The fires came after a string of very hot days that drove extreme drying of the vegetation, causing severe drought. Thunderstorms without precipitation generated lightning bolts that could have triggered the fires, though the cause is still under investigation. According to EM-DAT, here are the deadliest wildfire events in world history:

Rank Location Event Date Deaths
1 U.S. Forest fire October 15, 1918 1,000
2 Indonesia Forest fire September, 1997 240
3 China Forest fire May, 1987 191
4 Australia Bush/brush fire February 2, 2009 180
5 U. S. Forest fire October 20, 1944 121
6 France Wildfire August 1949 80
7 Australia Scrub/grassland fire February 16, 1983 75
8 Canada Great Porcupine Fire July 11, 1911 73
9 Australia Scrub/grassland fire 1939 71
10 Greece Forest fire August 24, 2007 65
11 Portugal Forest fire June 17-18, 2017 64

What is the lowest humidity ever recorded in Houston?


Justin Stapleton, Meteorologist



Tags: Ask 2, weather, Houston

Sign up for our Newsletters

9 minutes ago

KPRC 2 Pet Project: Meet Quincy, the charming pup!

2 hours ago

2 Friendswood PD officers injured after attempting to free victim from single vehicle crash, officials say

3 hours ago

Man rushed to hospital after apartment fire in northwest Houston, officials say

1 hour ago

Houston Newsmakers: John Whitmire readies for his run for Houston Mayor following departure from Texas State Senate

It’s not too late to get this day/night vision camera for an additional 20% off


KPRC 2 Meteorologist Justin Stapleton tackles your questions

Justin Stapleton, Meteorologist

Tags: Ask 2, weather, Houston


At KPRC 2, we’re dedicated to keeping Houstonians informed. As part of our new Ask 2 series, the newsroom will answer your questions about all things Houston.

The question: What is the lowest humidity ever recorded in Houston?

The answer: This question is something we get in the weather office from time to time so let’s break down the issue.

The agency that tracks weather extremes is the National Weather Service. For here in Houston, the KPRC 2 Weather Team works with our local forecast office, NWS Houston, where they track the daily weather, including days of extreme weather and sometimes temperature.

Let’s start with a little background on what humidity is: Humidity is a measurement of the amount of water vapor in the air. Think of it as the “sticky» factor that you feel in the air, especially in the summer in hot and humid Houston.

The higher the humidity, the more moisture that is in the air, the “swampier” it feels when you’re out in it. This is why we show the heat index on the weathercasts. The more water in the air, the hotter it feels and can become dangerous leading to conditions like heat exhaustion or even a deadly heat stroke.

Now, let’s flip that equation: The less water vapor in the air, the drier that air is and feels. If you have ever traveled out to the desert southwest in the United States, this is a way of life. Humidity levels generally remain very dry, with the moisture content of the air usually less than 25%. That is why if you’re traveling through let’s say, Arizona, you may feel like you always need to be drinking water, or if your lips are chapped, it is because the air remains very dry.

Generally, that isn’t something we deal with here in Houston, given how close we are to the Gulf of Mexico which is generally the source of warm, moist air that dominates our weather pattern most of the year. However, there are times when we are able to tap into a very dry air, generally from a passage of a cold front and a strong, dry, and sometimes cold high pressure center that moves in and removes a good chunk of the water vapor in our air.

Now to the unfortunate news: We did some digging with help from our friends from the National Weather Service, but unfortunately, they don’t keep records for things like humidity, usually, just for extremes with temperature, rainfall, and severe weather events. However, if I were to wager a guess, the lowest ever would be either sometime in possibly spring time when we have had a storm pass and a strong, dry wind is moving through, or also potentially in that ridiculously hot summer of 2011 when we were so dry that temperatures spiked from 107 to 109 on August 27th through the 31st.

Relative Humidity Guide

Do you have a burning H-Town-related question? Send it our way, and we will try to hunt down an answer.

Copyright 2020 by KPRC Click2Houston — All rights reserved.

About the Author:
Justin Stapleton

Meteorologist, craft beer guru, dad to Maya and Ella and a sock and cheese addict.

What humidity should be in the apartment: the norm, how to measure




Real estate

TV channel





New economy


Real estate



National projects



Debating Club


Credit ratings



Special projects St. Petersburg

Conferences St. Petersburg

Special projects

Checking counterparties

RBC Library


ESG index




Technology and media


RBC Company



Both too dry and too humid air in an apartment has a negative effect on the well-being of residents. RBC-Nedvizhimost tells how to ensure optimal humidity

Photo: Shutterstock

The comfortable temperature in the house is much more often in the field of view of the owners than the level of humidity, but in vain. Colds, exacerbation of allergies, headaches — these and other symptoms may indicate precisely a lack or excess of moisture in the apartment.

  • Humidity standards
  • What determines the humidity in the apartment
  • How to measure
  • Why high humidity is dangerous
  • How to downgrade
  • nine0083 Why low humidity is dangerous

  • How to upgrade

Humidity standards in the apartment


The norms of humidity in a residential area according to GOST are 30–45% in winter and 30–60% in summer. A significant excess is considered to be more than 60% in winter and more than 65% in summer.

The optimal level of humidity in the apartment is from 40% to 60%. The figure may vary depending on the season, weather and room format:

  • kitchen / bathroom — 40-60%; nine0084
  • living room — 40-60%;
  • bedroom — 40-50%;
  • for children — 45-60%;
  • office — 30-40%.

Photo: Shutterstock

What determines the humidity in the apartment

Many factors influence the level of humidity in the room:

  • season. In winter, humidity is lower because cold air holds less water vapor than warm air;
  • living conditions. Humidifiers help to increase the humidity in the apartment. Heating appliances, on the contrary, dry the air; nine0084
  • geographical location. In tropical latitudes, the level of humidity is higher than in the northern ones, and the presence of a reservoir near the house helps to normalize the amount of water vapor in the air.

How to measure humidity in an apartment

You can determine the level of humidity both independently and with the help of special devices.

Traditional methods:

  • Pour water into a glass and put it in the refrigerator for three hours. Then the glass is placed away from the heating appliances. If after five to ten minutes there is no condensation on the walls, the room is too dry, if there is, the humidity level is within normal limits. High humidity is evidenced by trickles of water into which condensate has turned; nine0084
  • wash bedding and measure how long it takes to dry. If it is about an hour and a half, then the humidity level in the apartment is low;
  • put the spruce cone away from heat sources and after a couple of hours pay attention to the scales. With an excess of moisture in the room, they will shrink, but if the air is too dry, they will open;
  • take a closer look at synthetic clothing — if the air is too dry, it is highly electrified;
  • nine0083 pay attention to indoor plants — against the background of a too dry climate, the tips of their leaves may turn yellow and become dry.

Photo: Shutterstock

Special instruments

Traditional methods only give a general idea of ​​​​the level of humidity — a hygrometer will help you find out the exact numbers. These devices are of several types:

  • digital, measures both humidity and room temperature;
  • hair, it is based on synthetic fibers, and it does not need electricity to work; nine0084
  • thermohygrometer — using a special signal, the device notifies you of deviations in the humidity level from the norm;
  • humidifier with a built-in mechanism for measuring the level of moisture in the air;
  • Assmann psychrometer. Two thermometers are combined in it with the help of a metal case, which show the level of humidity in the room. Differs in the increased accuracy of measurements.

Any device must be placed away from heating and heating devices and from drafts. So the readings will be more accurate. nine0003

Why is high humidity dangerous?

  • exacerbates asthma and chronic bronchial diseases;
  • increases the risk of exacerbation of allergic reactions;
  • possible poisoning by toxic fumes that are released from building materials at high humidity; nine0084
  • If sports activities are held in a room with high humidity, this may threaten with heat stroke.
  • How to remove the humidity in the apartment

    There are several ways to reduce the humidity in the apartment:

    • ventilate the room regularly. It is advisable to do this at least three times a day, be sure to go to bed and in the morning after getting up;
    • purchase an air dryer;
    • check the operation of hoods in places with potentially high humidity — in the kitchen and in the bathroom; nine0084
    • turn on the air conditioner or heater more often, they dry the air;
    • to dry clothes only on the balcony.

    Photo: Shutterstock

    Why is low humidity dangerous? This complicates the course of colds, asthma, SARS, diseases of the bronchi and lungs; nine0084

  • there is a feeling of dryness in the nasopharynx, local immunity decreases, which makes it much easier to get infected with infectious viral diseases. Dry eye syndrome may also develop, which can lead to the development of other eye diseases;
  • skin diseases become aggravated, peeling may appear, brittleness and dryness of hair may develop;
  • Allergies are more likely to aggravate, since respiratory allergens are much more active in dry air;
  • nine0083 efficiency decreases, weakness and headaches appear, sleep worsens;

  • due to dry air, bacteria and viruses are more mobile [1], which significantly increases the risk of infection. Their concentration is minimal if the air humidity is from 40% to 60% [2].
  • How to increase the humidity in the apartment

    There are many ways to increase the humidity in the apartment:

    • keep the bathroom door open. This will help to normalize the level of humidity both in the shower room and in the entire apartment due to the spread of steam throughout the room; nine0084
    • put indoor moisture-loving plants at home, which need to be sprayed and watered often;
    • buy an aquarium, put a table fountain or any water container in the room where humidification is required;
    • spray water twice a day in rooms with a spray bottle;
    • do wet cleaning more often;
    • distribute hydrogel balls around the house;
    • purchase a humidifier.

    See also

    How to humidify the air in your apartment: 10 life hacks

    Where microbes live: 10 dirtiest places in your house


    Diana Fastovskaya

    adv. rbc.ru

    Dermatovenereologist told why dry indoor air is dangerous — Moscow 24, 09/23/2021

    September 23, 2021, 09:30


    It is dank autumn outside the window, but it is warm in the houses. It would seem that we should rejoice in hot batteries, but the Russians are worried because of the undesirable influence of dry air. We figured out how to take care of ourselves during the heating season. nine0263

    Photo: depositphotos/yocamon

    Norm of life

    Experts say that if the humidity in the apartment in cold weather is from 40 to 60%, then there is nothing to worry about. However, people do not always have to live in normal conditions.

    «On average, indoor humidity during the heating season, unfortunately, is below 20-30%,» says dermatovenerologist Natalia Zhovtan.

    Excessive dryness immediately makes itself felt. According to the expert, as soon as the humidity falls below the 40% level, undesirable symptoms appear. In particular, people experience increased eye fatigue due to a decrease in the production of tear fluid. Many people complain of feeling as if they had sand in their eyes. nine0003

    «Dry crusts form in the nasal passages, itching and discomfort appear, the likelihood of nosebleeds increases,» says dermatovenereologist Natalia Zhovtan.

    Mucus, drying up, begins to irritate the membranes of the eyes and nose, and the person reflexively rubs them with his hands. In particular, children reach for their nose with their fingers due to itching and unpleasant crusts.

    Thus, the skin becomes an open gate for the penetration of infections into the respiratory tract and dermatological manifestations of bacterial and viral infections (pyoderma, molluscum contagiosum). nine0003

    Natalia Zhovtan


    In rooms with low humidity, people experience difficulty in breathing, sore throat, hoarseness of voice. This is especially dangerous for patients with asthma.

    Photo: depositphotos/tumsasedgars

    Bottom line

    Appearance is also affected by negative factors. According to the doctor, in a room with low humidity, the skin begins to dry out, evaporating its own water.

    «The skin becomes more sensitive and receptive to allergens and opportunistic microorganisms that live on it. This fact is especially unfavorable for people suffering from atopic dermatitis, skin xerosis, psoriasis and other skin diseases,» says the doctor. nine0003

    The dermatovenereologist emphasizes that aging processes are activated in heated rooms. Small wrinkles appear in the area around the eyes, cracks form in the corners of the lips.

    «The loss of moisture leads to the fact that blood circulation in the upper layers of the skin is disturbed. It receives less nutrients, which makes regeneration difficult,» explains Natalia Zhovtan.

    The expert notes that low humidity is also harmful to the hair. They become dry, thin and brittle. In the heating season, emollients come to the aid of the skin — products that moisturize the skin. According to the doctor, the daily use of these products immediately after water procedures significantly reduces the feeling of tightness and relieves itching. nine0263

    Photo: depositphotos/oksun70

    Help yourself

    According to the expert, it is important to know that humid air is always cleaner than dry air. Dust particles containing water vapor are heavier. They settle better on surfaces, and therefore regular wet cleaning helps during the heating season. In addition, clutter and the accumulation of a large number of soft toys, rugs and carpets should be avoided in the apartment. It is also necessary to regularly ventilate the room — 15 minutes twice a day. nine0003

    Sometimes housewives use a folk method of dealing with dryness — they cover the hot battery with wet towels. However, according to the dermatovenereologist, if you use this method, then only as an extreme and one-time measure.

    «There may be detergent residue in the fibers of the towel, which is extremely bad for breathing. And the fabric will dry on the battery in a matter of hours. So there will be no benefit,» the expert continues.

    According to Natalia Zhovtan, it is better to put a flat bowl of water on the windowsill above the battery for uniform evaporation of a clean liquid. nine0003

    «Today there are many modern ways to humidify and at the same time purify indoor air. For example, purchase household air humidifiers with various built-in filters that allow air to pass through and purify it from viruses and bacteria,» the doctor notes.

    Modern devices are equipped with a digital display indicating the temperature and humidity level in the room, they have additional options for air aromatization, they can be set to a convenient program. In budget options for humidifiers, you have to constantly update the water from which steam is generated, and all operations are performed manually.

    Добавить комментарий

    Ваш адрес email не будет опубликован. Обязательные поля помечены *