REX Weather Force: not Atmos, not Atmos CORE, and not in MSFS 2024

Three REX products currently sell for exactly $14.50, and two of them are called Atmos. This is the third one. Weather Force is not Atmos, it is not Atmos CORE, and buying it because you read a good review of one of those is the single easiest mistake to make in REX's catalogue — so before anything else: Atmos and Atmos CORE are atmospheric renderers. They colour the sky and reshape the clouds and they generate no weather at all. Weather Force is the opposite half of the problem. It is a METAR injection engine. It pulls real observations from NOAA six times an hour and forces them into the simulator, and it does nothing whatsoever to how the sky looks once they are in there.

REX's own pages say as much, quietly. The Atmos Legacy page lists Weather Force among the weather sources it can sit on top of. They are meant to be bought together, not instead of each other.

The decisive fact about Weather Force is on a different page again. Its last build is version 6.1.2024.0614 — Technical Update 7.0, dated 26 June 2024, five months before Microsoft Flight Simulator 2024 shipped on 19 November. Every store that sells it says MSFS 2020. REX's own support portal files it under the product name "Weather Force for MSFS 2020". And when REX published a 2026 product roadmap on 18 March this year, it listed feature updates one through six for Atmos Core and Atmos Legacy, and did not mention Weather Force once. What it did list, at Feature Update 5, is "Integration of Weather Core" — REX folding weather injection into the Atmos line rather than carrying the old engine forward.

So the obvious conclusion is that this is a dead product, and the obvious conclusion is wrong, which is the interesting part. On 13 July 2025 a poster on the official forums bought Weather Force on sale to test against default live weather at Genoa, and it worked: it put thunderstorms and lightning over the area the satellite imagery showed them, which the default engine did not. The licence servers, the download portal and the METAR feed are all still up. REX still lists Weather Force in the support-ticket dropdown at rexaxis.com in 2026, and on 20 July 2026 they put the entire MSFS 2020 collection on sale at $14.50 — Weather Force included. This is a frozen product, not an abandoned one. Whether that distinction is worth $14.50 to you depends almost entirely on which simulator you launch.

We read 27 sources for this: REX's own product, news and knowledge-base pages, six store listings, the published changelog, four AVSIM threads including the 16-page release argument, six threads on the official Microsoft Flight Simulator forums including REX's own 1,043-post announcement thread, three video reviews and two launch write-ups. Reddit is structurally unavailable to us, so the usual sentiment-at-a-glance check is missing; in its place we leaned on simMarket's fifteen customer ratings, which are unusually blunt.

What you are actually buying

A Windows desktop application, 17.59 MB, that talks to Microsoft Flight Simulator 2020 by inter-process communication and overwrites the simulator's weather. You run it alongside the sim with MSFS's own live weather switched off. It downloads METAR from NOAA six times an hour and GFS model data from NCEP twice daily, blends the two to fill oceans and deserts, and injects the result.

Store	Price	Notes
REX Simulations direct	$14.50	The developer's own store; "last items in stock" is a shop-software artefact, not a real limit
Just Flight	US$14.50	Also hosts the official changelog
Aerosoft	$14.50	Product page still advertises version 6.0 from 26 March 2023 — a build behind
Contrail	$15.12	5 stars from 4 votes
Orbx Direct	A$20.85 (about €12.71 / £10.89)	Installs through Orbx Central
simMarket	€18.87	No sale badge, no 30-day-low field — this is simply simMarket's standing price

That last row deserves a sentence of its own. We checked simMarket's listing for a discount marker and there is none: no struck-through price, no percentage badge, no 30-day price low. €18.87 is what it costs there, and it is roughly half again what Orbx quote in the same currency for the same file. simMarket's terms note that displayed prices include whatever VAT applies, which is 0% for a browsing session with no account resolved, so this is not a tax artefact either. Buy it from REX, Just Flight, Aerosoft or Orbx.

Launch price was $21.95 on 26 September 2020. It has come down, not up.

In the box: live METAR injection; nine dynamic changing weather scenarios (fair weather, approaching cold front, approaching warm front, hot and humid summer, lake effect snows, winter storm, crisp winter, breezy, spring showers); a five-year historic weather archive; snow depth control; a search tool that finds airports by weather criteria rather than by name; and tracking for ten favourite airports.

There is no upgrade path. REX's Atmos CORE discount — 50% off, or about €6.21 at simMarket — requires a valid Atmos 2020 licence. A Weather Force licence unlocks nothing.

What the community consistently praises

The core claim holds where it is tested. In January 2022, in a thread whose title was literally "Sell Me REX Weather Force" and whose replies were overwhelmingly hostile, AVSIM member MrBitstFlyer posted a side-by-side: real conditions were a low broken cumulus layer under a high overcast, MSFS live weather drew one wrong cloud type with no layering, Weather Force drew both layers correctly. His summary — that Weather Force "portrays the weather in a much more realistic and accurate way than MSFS Live Weather" — is the most detailed defence in the record, and it came from someone who had just listened to eight people tell the original poster not to buy it. Three and a half years later the July 2025 tester reached a compatible conclusion from the other direction: default MSFS drew scattered cloud in the middle of a thunderstorm complex, and Weather Force at least produced the storms.

Its second life is as a failover. Between 2021 and 2023 MSFS 2020's live weather went down repeatedly, and Weather Force is what people reached for. That recommendation appears in the official bug thread for live weather failing mid-flight in February 2023, in the AVSIM sell-me thread, and from at least four separate posters in REX's own announcement thread — including some who were otherwise critical. "It's a pretty good backup if MSFS No 1 Feature went offline," as one put it in August 2023. Nobody disputes this use case.

Then there are the features MSFS 2020 does not have and never got. Five years of archived weather, so you can re-fly a real flight in its real conditions. A snow-depth control, which matters more than it sounds: one Alaska flyer stayed on Weather Force specifically because MSFS could not stop putting snow on the Arctic in August. And a search that answers "where is it currently raining hard" rather than "what is the weather at KJFK".

One more thing, and it is worth saying because it is the opposite of what we found reviewing REX's other products: nobody complains about the interface. When Weather Force is called "a hack with a pretty interface", the insult is aimed at the first half. Our reviews of REX Atmos and Atmos CORE both turned on interfaces that paying customers called among the worst they had used. Weather Force's is fine.

What keeps coming up as a problem

Weather changes in a jolt, not a gradient. Still open. This is the single most repeated complaint in six years of record, and it starts on day one — a simMarket reviewer on 10 October 2020, two weeks after release, described flying past Boston and watching the entire sky flip from clear to overcast and back as the engine picked up KBOS and then dropped it. It is still being described in identical terms in Chinese, German and English simMarket reviews from 2023. The marketing word for what the product does here is "smooth". The community word is "abrupt".

Global injection: one sky in every direction. Still open, and structural. Weather Force applies a single weather state to the entire visible world, taken from the nearest reporting station. As a poster summarised it in REX's own thread in September 2023: it does "global injection, not area specific injection", so if it is clear at the station and foggy ten miles away, you get clear everywhere until you cross into the next station's territory. The July 2025 tester found the inverse — storms correctly placed around him, and "a big blue hole in the skies just at the airport it pulled the metar from". This is the same limitation Active Sky FS lives with on MSFS, and for the same reason: Asobo never exposed a weather API that would let anyone paint a front.

Winds. Still open. Two independent failure modes. Surface winds were reported as roughly half real strength in December 2022, and a simMarket reviewer in November 2023 said there was no wind at all below 10,000 feet. Separately, in February 2023 winds aloft stopped arriving entirely — flat surface wind all the way to FL390 — and a poster reported REX had acknowledged on Discord that they were not receiving the morning data dumps. That one appears to have resolved; the data feed is demonstrably alive now. The general wind inaccuracy was never fixed.

It takes the simulator's live weather away from you, and other things with it. Still open. Weather Force needs MSFS live weather off and the Clear Skies preset selected. A simMarket reviewer in September 2021 docked it a star because that combination also killed live traffic; a poster on the official forums in January 2024 found it degraded contrail rendering for the same reason. Neither is REX's fault, exactly. Both are things you lose.

Aircraft misbehaving on weather updates. Mostly mitigated, one item officially open. In November 2022, after Sim Update 11, a CRJ-900 flyer reported engines shutting down and ITT errors on every weather refresh. A simMarket reviewer in January 2022 reported wind shifts violent enough to take control of the aeroplane. Most of this quietened after the 2023 builds. The altimeter version did not: REX's own knowledge base carries an article dated 10 February 2023, severity High, applying to all builds, titled "Rapid Altimeter Changes". REX blame the simulator's five-minute altimeter refresh and their published solution is to press B during the flight. That is a workaround, not a fix, and it is three and a half years old.

Promised features that never arrived. Still open. The product page still carries the launch-day heading "The following is a list of updates coming soon after initial release", followed by three items: historic weather, community preset sharing, and a "full featured flight center and mapping system". Historic weather shipped, in Technical Update 7.0 in June 2024, three years and nine months later. The other two never did, and the words "coming soon" are still on the page today.

Performance and stability

This is the section that decides the score, and REX have already written it for us.

Their knowledge base carries an article dated 23 May 2023, product "REX Weather Force for MSFS 2020", version "All Builds", severity level Critical, titled "Frame rate drop - FPS". The issue: "Experience frame rate drops when Weather Force injects weather into the simulator." The solution, in four bullets: lower your resolution, reduce your settings, disable VSync, lower your render scaling. There is no fifth bullet in which REX fix anything.

The community record matches it exactly and predates it by years. "The FPS was brutal," from a customer in November 2022 who bought at launch and had stopped using it. "80 FPS to 40 FPS, with occasional dips down to a herky-jerky 10 FPS" flying into cloud, September 2023. "Frame rates become choppy no matter which setting combination I try," from a January 2022 poster on an i7-10700KF with a 3070 — hardly a marginal machine. That poster added the detail that makes the whole thing circular: the fix REX support offered him on Discord was to switch weather transitions from gradual to instantaneous, "which kind of defeats the purpose". A second poster independently confirmed the same trade in September 2023. You can have smooth transitions or you can have your frame rate. Not both.

Crashes are rarer but real: one poster in September 2023 reported the application falling over on any significant change in the sim, and a March 2022 poster lost weather entirely an hour into a flight with no way to get it back.

One live-service wobble is worth logging. On 11 March 2025 a customer posted a screenshot of Weather Force displaying a "TEST VERSION" watermark despite owning the licence, reinstalling to no effect, and finding only a "repeat order" button in his store account. Nobody answered him. That post is, as of today, the last message in a thread that ran to 1,043 posts and 26,500 views.

Who should buy it

If you fly MSFS 2024, do not buy this. Not "consider the alternatives" — do not buy it. There is no MSFS 2024 build, there has never been one, and in the twenty-one months since MSFS 2024 launched, a search of the official forums returns not one thread pairing the two names. Active Sky FS covers both simulators on a single licence for about €25 and is the only serious answer here. If what you actually wanted was better-looking sky in 2024, that is Atmos CORE at $14.50, and it is a different product doing a different job.

If you fly MSFS 2020 and want historic weather, buy it. This is the profile the product still serves cleanly. Nothing else lets you set a date in the last five years and fly the conditions that actually existed, and $14.50 is a fair price for that alone.

If you fly MSFS 2020 and got tired of live weather dropping out, buy it, and expect to use it perhaps one flight in ten. That is how most of its remaining defenders describe their own usage, and there is no shame in it.

If you fly MSFS 2020 at 4K on high settings, think hard. REX's own Critical-severity advice to you is to turn your settings down. If you are not willing to do that, the transitions you are paying for are the first thing you will disable.

If you are a low-level VFR pilot who flies to watch weather arrive, this is not it. One sky in all directions means nothing ever approaches. That limitation belongs to the platform rather than to REX, but you still will not get what you want.

If you already own Atmos or Atmos CORE and assumed this was the same family, stop here. It is a complement, not an upgrade, and it buys you nothing in MSFS 2024.

Where it stands today

Weather Force sits in an unusual place: frozen, supported, and quietly on its way to being replaced by a feature inside something else. The code has not moved since 14 June 2024. The documentation has not moved since May 2023. But the servers run, the ticket queue accepts it, REX put it back on sale a month ago, and a buyer in July 2025 got real thunderstorms out of it. We have reviewed products in this series whose weather feed had simply been switched off; this is not one of them.

What has changed underneath it is everything else. MSFS 2020's live weather was genuinely poor in 2020 and genuinely unreliable in 2022, which is the entire market Weather Force was built for. By 2023 the honest answer to "how does it compare to base weather" was, from a long-term user in REX's own thread, "base weather is better." By 2026 the argument has moved on so completely that when an AVSIM poster opened an 88-reply thread on 2 April this year explicitly asking whether he could still use Weather Force alongside Active Sky and Atmos Core, nobody in the first three pages answered the question. The last video review of any substance is four years old.

Then there is REX's own roadmap, which is the clearest statement of intent available. Six feature updates planned for 2026, all of them for Atmos Core and Atmos Legacy, and the fifth is the integration of a component called Weather Core. REX are not going to update Weather Force for MSFS 2024. They are going to rebuild what it does inside Atmos. If that lands, Weather Force becomes the last MSFS 2020 artefact in a catalogue that has otherwise moved on — still working, still sold, still $14.50, and still, for the specific person flying MSFS 2020 who wants a weather archive and a live-weather backup, quietly worth the money.